S I G A N A T u R A l S l A T E A G U I D E

Transcription

1 S I G A N A T u R A l S l A T E A G U I D E

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3 S I G A N A T U R A l S l A T E A G U I D E Cotets 5 Itroducig SIG Roofig 5 A Itroductio to SIGA Natural Slate 6 Uderstadig BS EN12326 & CE Markig 9 Slate Selectio ad Wastage Rates 10 Desig Cosideratios 11 Fixigs ad Headlap Tables BS Fixig Natural Slates 16 Slate Storage ad Sortig 17 Slate Coverage 19 SIGA Rage Overview 19 Excellece Rage 20 Specificatio Rage 21 Commercial Rage 22 Ecoomy Rage

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5 S I G A N A T U R A l S l A T E A G U I D E SIG Roofig SIGA Natural Slate Itroducig SIG Roofig As the largest distributor of atural slate i the world, the SIG Group supports Europe s largest markets, icludig the UK, Irelad, Frace ad Germay. SIG Roofig, a subsidiary of SIG plc, sells over 13 millio slates a year across the UK from a rage, largely sourced directly from the quarries. Quality is at the forefrot of everythig we do, so we work closely with our producers to esure that we supply slate that ot oly meets your performace criteria, but also meets your aesthetic requiremets withi budget. We kow from our extesive experiece that o two projects are alike, so we esure that every slate is carefully selected to match your roofig requiremets ad geographical area. A Itroductio to SIGA Natural Slate Slate is a atural material ad will vary i quality ad selectio. Whilst some variatio is ormal, our costat iteractio with the quarries esures that both selectio ad quality are cosistet. All SIGA slates meet key essetial criteria: BS EN12326 test results ad certificatio (see ext sectio) CE labellig Cosistecy ad security of supply Cosistecy of quality SIGA Natural Slate is sourced from all over the world. Major slate producig coutries iclude Spai, Wales, Brazil, Chia ad Caada. A SIGA umber specifically defies the quarry ad selectio of slate, guarateeig traceability ad cosistecy that is secod to oe. I order to further cemet our commitmet to provide quality atural slate, we lauched our Slate Operatios Cetre, SIG Pizarras i Through SIG Pizarras, based i the heart of the slate quarryig regio i Leo, Spai, we have access to: A wide rage of quarries for all types of slate O-site full-time quality cotrol persoel Highly experieced slate procuremet persoel Custom slate sizes, headlaps ad selectio Rapid ad efficiet logistics Our UK slate operatios are combied uder the established market leadig brad SIGA. The SIGA brad is syoymous with: Cosistecy of quality Logevity of supply Best value Choice ad variety Traceability

6 6 Uderstadig BS EN12326 & CE Markig BS EN12326: 2004 This stadard is desiged to eable the specifier / purchaser to compare the key physical properties of atural slates to esure the best fit for the project. A broad rage of attributes are tested, but the three most critical areas are Thermal Cycle, Sulphur Dioxide Exposure ad Water Absorptio. BS EN12326 replaced the previous slate stadard, BS 680, i ermal Cycle Essetially, this process assesses the levels of rust or oxidisatio withi the slate. The test ivolves repeatedly soakig six pieces of slate i water ad the dryig them out over a period of up to three weeks. The samples are the ispected for corrosio. The results are classified as follows: T1: No apparet chage OR some surface rust OR other colour chages that either affect the structure, or form rus of discolouratio. T2: Oxidatio or appearace chages of the metallic iclusios with rus of discolouratio but without structural chages. T3: Oxidatio or appearace of chages of metallic mierals that peetrate the slate ad risk formig holes. SIG Roofig does ot supply ay T3 slates. All SIGA slates have bee idepedetly tested to T1 or T2 stadard. Sulphur Dioxide Exposure This test examies the ability of the slate to resist atmospheric pollutats. The slate samples are placed i a hermetically sealed cotaier for up to three weeks ad subjected to extreme acidic ad humid atmospheric coditios. These samples are the subjected to a stadardised mechaical scrapig test to measure ay softess caused by the chemical disitegratio of ay carboate cotet. Results are show as S1 (o chage), S2 (the slate must be split at least 5% thicker) or S3 (slates must be at least 8mm). Slates cotaiig more tha 20% carboate cotet are ot suitable for roofig or exteral claddig. All SIGA slates have bee idepedetly tested to S1 stadard. Water Absorptio Excessive water absorptio will result i atural slate beig vulerable to frost damage. If the slate absorbs 0.6% or less of its mass i water, it is classified as A1, the highest grade, ad eeds o further testig. If the absorptio is greater tha 0.6% it is classified as A2 ad must be subjected to a separate freeze-thaw test, showig o deterioratio i mechaical stregth. All SIGA slates have bee idepedetly tested to A1 stadard.

7 S I G A N A T U R A l S l A T E A G U I D E CE Markig Uder the Europea Costructio Products Directive, ay orgaisatio that produces, imports, or sells atural slate must esure that CE Markig ad certificatio are sought ad displayed. Purchasers ad istallers of Natural Roofig Slate ca check whether the slates they have purchased, or are usig, have bee tested to BS EN12326 by lookig for the CE markig o ay labels withi the packagig, ad/or ay documetatio accompayig the Most SIGA slates are classified as T1 for miimal surface corrosio, although some T2 slates are available for the more cost coscious customer. All SIGA slates are classified as S1 for stregth after corrosive BS EN : 2004 is the harmoised EU stadard goverig Natural Slate ad Stoe for Discotiuous Roofig ad Claddig. All slates, irrespective of their origi, should be tested to the criteria laid dow i the stadard, ad thus have a set of test results ad carry the CE mark. slates, such as delivery otes or ivoices. Please ote that CE markig does ot idicate the quality of a slate but that it has bee tested to BS EN12326: Summary: All SIGA slates are tested to BS eviromet exposure. All SIGA slates are classified as A1 for water absorptio. I respose to problems caused by poor quality slates o ew homes, the NHBC ow require that all slates used o NHBC-covered projects are A1, T1, S1 accordig to BS EN12326, ad that valid Accompayig UK Buildig Regulatios have bee ameded to esure that oly CEmarked products are used i cases where a directive exists. Local Authority Buildig Cotrol EN12326: 2004 ad test results are readily available. All SIGA slates carry the CE mark. Every crate of SIGA slates is marked with EN test results. Commercial Documets are provided. The SIGA rage icludes a wide variety of A1, T1, S1 slates to suit local requiremets. Departmet eforce these regulatios, so we recommed that you esure that ay atural slate you specify carries the CE mark, ad your supplier provides a set of test results. Declaratios of Coformity I additio, the BS EN12324: 2004 stadard makes referece to Accompayig Commercial Documets, which are a comprehesive summary of the test results. These are updated o at least a aual basis as ew test results are published. All SIGA Declaratios of Coformity are available upo request from SIG Roofig braches, ad from our website

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9 S I G A N A T U R A l S l A T E A G U I D E Slate Selectio ad Wastage Rates Every quarry grades their slates ito 'selectio' durig the productio process. As there is o Europea or idustry bechmark, there is little or o cosistecy across the market defiig what makes a particular grade. Every quarry will aim to produce the highest possible proportio of best quality slates, with the lower grade slates more keely priced. However it is importat to ote that ay potetial savigs made from usig lower grade slates may be offset by icreased time ad labour charges ivolved i additioal sortig ad gradig. To esure you have greater trasparecy whe selectig atural slate, all SIGA slates are categorised ito 'Excellece', 'Specificatio', 'Commercial' ad 'Ecoomy'. Depedig o the quarry (ad eve the seam of rock i that quarry), the selectio process usually results i a mixture of the followig grades: Excellece Specificatio Commercial Ecoomy With a 'Buildig Lifetime All our Specificatio Slates Ideally suited to professioal The lowest priced SIGA Warraty', these T1, S1, A1 are T1, S1, A1 rated, which istallers, these are good slates, Ecoomy slates ca rated slates are of the allows uiversal use o quality slates with up to a 50 require a great deal of highest quality from the NHBC ew build work ad year warraty, ad ca sortig ad gradig i order fiest quarries. Wastage offer a competitive istalled provide a ecoomic to produce a good roof rates are extremely low cost due to low wastage. solutio to both ew ad fiish. These are ideal for oce cuts for eaves, hips refurbishmet work. small patchig jobs or low ad ridges are take SIGA commercial slates are cost refurbishmet work. ito accout. rated to T1 or T2 Availability ad cotiuity is classificatio, with a distict ot as cosistet as the price advatage over our better rages of slate, but specificatio ad excellece all SIGA Ecoomy slates rages. However, additioal must meet the same strict costs required to sort, grade testig ad certificatio ad istall should be take criteria. The majority are ito accout. rated as T2. Cost Wastage Excellece Specificatio Commercial Ecoomy Slate cost Fiished roof cost Wastage Note: all atural slates must be sorted prior to istallatio. Whe decidig o the most appropriate slate we recommed that you cosider all of the costs associated. These iclude wastage rates, gradig, sortig ad trimmig required with the lesser quality slates alog with trasportatio costs eeded for distributio.

10 10 Desig Cosideratios 26 Categories of exposure to drivig rai ad basic wid speeds 25 Lododerry Belfast 29 Oba Glasgow Exposure zoes Iveress Aberdee 23 Dudee Perth Ediburgh Carlisle Newcastle 24 York Kigsto Presto 23 Leeds upo-hull Liverpool Machester Sheffield Stoke Nottigham Leicester Norwich Birmigham Aberystwyth Northampto Ipswich Bedford 20 Oxford Swasea LONDON Cardiff Bristol Plymouth Bouremouth Brighto Approximate volume of wid-drive rai (litres/m 2 per spell) Less tha 56.5 (sheltered/moderate) More tha 56.5 (severe/very severe) (Categories derived from BS 5534: Part 1) Basic wid speeds 31 Basic wid speed V(i m/s) b (Derived from BS 6399: Part2) To esure the effective desig of a atural slate roof, it is imperative that key iterrelated factors are take ito accout icludig: Site exposure The pitch of the roof The type of slate selected The slate lap Geeral guidace o the most importat poits to be cosidered is give below. Further iformatio ca be obtaied from BS 5534: 2003, Code of practice for slatig ad tilig. Evirometal Coditios Rai exposure The degree of exposure of a buildig to drivig rai determies the miimum lap which should be specified. The aticipated degree of exposure is give i the adjacet image. Localised factors such as high buildigs, buildigs o the slopes or tops of hills ad coastal sites, ca icrease the exposure gradig which should be applied i a specific project. The table o page 12 shows the miimum recommeded headlap for moderate ad severe exposure sites. Pitch of roof I geeral, the lower the pitch of the roof, the greater should be the lap. This loger lap will help to resist both capillary actio ad wid uplift. O steeper pitches with free-flowig draiage, smaller slates may be used. For exposed sites, wide slates with a greater lap should be used, whereas i sheltered areas, roof pitches as low as 20 degrees ca be achieved usig a hook fixig system. lap The lap is calculated by takig accout of wid uplift, exposure to drivig rai ad the roof pitch. The table o page 12 gives the recommeded miimum laps for various roof pitches ad buildig exposures.

11 S I G A N A T U R A l S l A T E A G U I D E Fixigs ad Headlap Tables BS 5534 BS 5534: 2003 is the Code of Practice for Slatig ad Tilig ad describes ot oly the meas of istallig slates (ailig or hook fixig), but also the 'headlaps' required to esure that the roof remais watertight eve at pitches as low as 20 degrees. The most commoly used slate size i Britai is 500 x 250mm. Most stock slates will be pre-holed at 75, 90 or 100mm, allowig you the versatility of differet pitches - 25 degrees i moderate exposure zoes ad 30 degrees i severe exposure zoes. The actual differece i the locatio of the holes betwee 75 ad 100mm headlap slates is oly 12.5mm. We recogise that most battes used i ew builds are 50mm wide ad supply a rage of SIGA slates with a uiversal headlap of 90mm. This allows the slater to istall a sigle pre-holed slate at a variety of headlaps, simply by movig the slate further up or dow the batte. We offer the majority of our SIGA slate at a sigle headlap, thus providig you with greater flexibility of choice. We ca also pre-hole ay headlap to special order. While this does ot ormally attract a price premium, ay bespoke products must be ordered i advace to esure timely delivery for specific projects. Termiology This diagram gives a brief explaatio of the terms that are commoly used throughout the roofig idustry. However, differet regios may use differet ames, so we always recommed that you refer to BS 6100: subsectio 1.2.3: 1989 Buildig ad civil egieerig terms roofs ad roofig. 20 to 25mm head 8 to 15mm gauge head lap holig gauge = gauge + lap + 8 to 15mm margi tail bod/side lap

12 12 Miimum Recommeded Headlaps These tables give miimum recommeded headlaps accordig to exposure, roof pitch ad slate size. Detailed guidace o wid load calculatios is give i BS 5534: 2003 ad BS EN Slate Size Moderate Exposure (less tha 56.5l/m²/spell) Pitchº mm iches (approx) 600x300 24x12 * x300 20x x250 20x x250 16x x220 18x x220 16x x200 16x x250 14x x200 14x x200 12x Slate Size Severe Exposure (56.5l or more /m²/spell) Pitchº mm iches (approx) 600x300 24x12 * x300 20x x250 20x10 * x250 16x x220 18x x220 16x x200 16x x250 14x x200 14x x200 12x Notes from BS5534: The Miimum Roof Pitch for Natural Slates: 20 degrees (BS5534: 2003 Page 27) Depedig o Size of Slate See Table Above (BS5534: 2003 Page 27, Table 5). 2. Slates 450mm Log or Less Should Not Be Used at Pitches Of 27.5 Degrees or Less (Moderate & Severe Exposure) (BS5534: 2003 Page 27, Table 5). 3. Slates less tha or equal to 460mm log or greater tha 450mm log should ot be used at pitches of 25 degrees or less i Severe Exposure (BS5534: 2003 Page 27, Table 5). 4. Slates less tha or equal to 500mm log or greater tha 460mm log should ot be used at pitches less tha 25 degrees i Severe Exposure (BS5534: 2003 Page 27, Table 5). 5. Table to be Used for Buildigs with a Maximum Ridge Height of 12 metres ad Rafter Legths ot loger tha 6 metres i Severe Exposed areas ad ot loger tha 9 metres i Moderate Exposed areas (BS5534: 2003 sectio 5.3.1). 6. Where abormal weather coditios might be expected, e.g. o elevated sites, ear to the coast, i localities where heavy sow falls are commoly experieced or i coditios of severe exposure, the followig recommedatios for pitches ad laps will ot always esure full protectio from the weather. I such coditios, the specifier usig geeric products should seek guidace from a competet perso who is coverset with local coditios ad ay special precautios that should be take ito accout i desigig the roof coverig (BS5534: 2003 sectio 5.3.1). * Please cotact us for advice

13 S I G A N A T U R A l S l A T E A G U I D E Batte ad Holig Gauges mm Iches 50mm lap 55mm lap 65mm lap 70mm lap 75mm lap 80mm lap 85mm lap 90mm lap 95mm lap 100mm lap 105mm lap 110mm lap 115mm lap 120mm lap 125mm lap 130mm lap 150mm lap Slate Legth Batteig gauge (mm) (M) batte per sq.m Holig gauge (mm) Batteig gauge (mm) (M) batte per sq.m Holig gauge (mm) Batteig gauge (mm) (M) batte per sq.m Holig gauge (mm) Batteig gauge (mm) (M) batte per sq.m Holig gauge (mm) Batteig gauge (mm) (M) batte per sq.m Holig gauge (mm) Batteig gauge (mm) (M) batte per sq.m Holig gauge (mm) Batteig gauge (mm) (M) batte per sq.m Holig gauge (mm) Batteig gauge (mm) (M) batte per sq.m Holig gauge (mm) Batteig gauge (mm) (M) batte per sq.m Holig gauge (mm) Batteig gauge (mm) (M) batte per sq.m Holig gauge (mm) Batteig gauge (mm) (M) batte per sq.m Holig gauge (mm) Batteig gauge (mm) (M) batte per sq.m Holig gauge (mm) Batteig gauge (mm) (M) batte per sq.m Holig gauge (mm) Batteig gauge (mm) (M) batte per sq.m Holig gauge (mm) Batteig gauge (mm) (M) batte per sq.m Holig gauge (mm) Batteig gauge (mm) (M) batte per sq.m Holig gauge (mm) Batteig gauge (mm) (M) batte per sq.m Holig gauge (mm)

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15 S I G A N A T U R A l S l A T E A G U I D E Fixig Natural Slates BS 5534 specifies two ways of istallig slates: ailig or hook fixig. These fasteers fix the slates to either batte which is by far the most commo Eglish method, or to sarkig board, which is commoly used i exposed areas i Scotlad. Nailig Nail fixig is the traditioal UK method of istallig slates ad requires a degree of skill to produce a professioal result. Most SIGA slates are supplied pre-holed. Thier slates (up to 7mm) are usually puched from the reverse face, creatig a small spalled area aroud the hole to allow the head of the ail to sit flush with the face of the slate. Thicker or very hard slates are ofte drilled. To comply with BS 5534, ails used for slatig must: Be made from copper or alumiium. Steel (icludig galvaised steel) is ot permitted for reasos of corrosio, ad hece safety. Have a shak (wire) diameter of at least 3mm. Have a head diameter of at least 10mm. Be of the correct legth to egage ito a stadard 25 x 50mm batte by 20-22mm. SIGA slate stockists carry RoofShop ails made to these specificatios, maufactured i the EU, ad fully compliat with BS Hook Fixig Hugely popular i cotietal Europe, hook fixig is quicker ad simpler to istall tha ail fixig. It provides additioal security should a slate crack, as it prevets the loose tail of the slate from fallig off the roof. I additio, hook fixig reduces the risk of slate breakage durig ailig with covetioal pre-holed slates. To comply with BS 5534, hook fixigs must: Be made from 316-grade (Marie Grade) stailess steel. Have a spiked ed (drive ito the batte/sarkig board like a ail), ot batte ed (where the top part of the slate hook wraps aroud the batte). There are several grades of stailess steel from which slate hooks have bee made. While 316-grade stailess steel is absolutely essetial i corrosive atmosphere (e.g. cities, coastal areas), 304-grade has bee safely used i ilad rural areas, ad ca offer a modest cost savig. Lower grades of stailess steel become brittle with time, leadig to slate loss ad the risk of accidets. SIGA slate stockists carry RoofShop 316-grade slate hooks made to these specificatios. These are maufactured withi the EU ad comply fully with BS 5534.

16 16 Slate Storage ad Sortig All atural slates should be sorted ad graded i accordace with BS This is most easily doe at groud level. Ay twisted or bowed slates should be set to oe side, ad be used first for eaves or top slates. This will result i the best possible roof fiish. Not sortig slates, particularly amogst the Commercial ad Ecoomy rages, ca compromise the aesthetic appeal of the roof. Slates should be stored i their pallets wherever possible. Oce removed from the crate, they should be stacked o their log edge o two pieces of batte. Each slate should be ispected ad separated ito three piles: Thick slates ideally should be used at the lower roof Medium thickess slates used i the middle of the roof Thi slates used o the upper roof

17 S I G A N A T U R A l S l A T E A G U I D E 400 x x x 300 Slate Coverage Give the multitude of differet sizes ad headlaps available, ad the peculiarities of the productio process, the istalled cost of ay slate ca be iflueced by the size selected, ad the quatity of batte ad fixigs required for that particular slate size. Please cotact your SIGA Slate Busiess Developmet Maager for further assistace. The most popular slate size i Souther Eglad is 500 x 250mm, ad 400 x 250mm i the North of Eglad ad Scotlad. Nomial Size Lap (mm) x x x x x x x x x x x x Values are calculated usig omial sizes ad icorporate a 5mm joit gap. We recommed usig wastage allowaces based o the guidace o page 9.

18 18 Warraty overview: SIGA slates, ad the quarries that produce them, have bee carefully selected by experieced specialists to satisfy our customer s roofig requiremets. Because of the traceability we rigorously eforce, SIG Roofig is able to provide a product replacemet warraty directly to the ed-user; givig the peace of mid you would expect with a leadig UKbased distributor. The warraty is i additio to, ad does ot affect, your statutory rights. Full terms ad coditios of the warraty are available o request.

19 S I G A N A T U R A l S l A T E A G U I D E SIGA Rage Overview Excellece Rage The fiest SIGA Slates from the most reputable quarries are selected to provide a log-lastig, beautiful roof with miimal gradig & sortig. The Excellece rage also provides a readily-available alterative to log-discotiued domestic British slates, with a close match for texture ad colour, without the slightest compromise o quality. The fiest Primera selectios from the very best quarries, the SIGA Excellece rage offers: Superlative quality stoe Exceptioal selectio with very low wastage Exteded warraties ad log life expectacy Spaish SIGA 12V Smooth, blue-grey slate from La Baña Regio, Spai. Approved for use i Sowdoia Natioal Park, with excellet quality sectio. SIGA 114 Very smooth, blue-black first selectio. Full A1, T1, S1 certificatio. Exceptioally smooth ad cosistet for a perfect fiish. Welsh SIGA 110 Hadmade i Wales exclusively for SIG Roofig by Greaves Portmadoc A idigeous radom width, dimiishig course, heavy slate for coservatio projects Approved by Historic Scotlad for use i Ediburgh city A uique, warrated, ad outstadig alterative to secodhad slate Close visual match for Ffestiiog slate with a rugged texture Backed by up to a 100 year warraty* o SIGA Excellece Rage *Terms ad coditios apply Cotact us for SIGA Datasheets ad Declaratios of Coformity.

20 20 SIGA Rage Overview Specificatio Rage A selectio of high-quality first-selectio slates, coverig a broad rage of colours ad textures to fulfil almost ay specificatio desired. The Specificatio rage is carefully tailored to each part of the UK, ad regioal favourites are stocked i depth for rapid availability ad service. SIGA Specificatio slates are a popular choice with homeowers, self-builders ad developers, due to their cosistecy, quality, smooth roof fiish, ad market-leadig warraties. All Specificatio slates are A1, T1, S1 to comply with NHBC requiremets. Backed by up to a 75 year warraty* o SIGA Specificatio Rage *Terms ad coditios apply Cotact us for SIGA Datasheets ad Declaratios of Coformity.

21 S I G A N A T U R A l S l A T E A G U I D E SIGA Rage Overview Commercial Rage A rage of affordable slates of good quality, ideal for the refurbishmet & volume developer market. These are recommeded for experieced slaters, as thickess ad quality ca be more variable tha the Specificatio rage, so careful sortig ad gradig is strogly recommeded for the best aesthetics. Most slates are A1 T1 S1 to comply with NHBC requiremets, but for refurbishmet work, the Commercial rage icludes some T2 slates with good workability ad cosistecy. Wastage, while still very reasoable, is geerally a little higher tha the Excellece or Specificatio rages. Backed by up to a 50 year warraty* o SIGA Commercial Rage *Terms ad coditios apply Cotact us for SIGA Datasheets ad Declaratios of Coformity.

22 22 SIGA Rage Overview SIGA Ecoomy Slates The lowest priced SIGA slates, Ecoomy slates ca require a great deal of sortig ad gradig i order to produce a good roof fiish. These are ideal for small patchig jobs or low cost refurbishmet work. Despite their lower price, all SIGA Ecoomy slates must meet the same strict testig ad certificatio criteria as the higher grades. As they are a by-product of the productio of the higher-quality slates, availability ad cotiuity is more fluid, so they are ot recommeded for very large or log-term projects. The majority of SIGA Ecoomy Slates are T2, ad as they are of the lowest merchatable quality, wastage rates will be cosistet with the quality of fiish required. The additioal cost of skilled labour should be take ito accout if Ecoomy Slates are beig cosidered. Backed by up to a 30 year warraty* o SIGA Ecoomy Rage *Terms ad coditios apply Cotact us for SIGA Datasheets ad Declaratios of Coformity.

23 SIG Roofig, Hardig Way, St Ives, Cambridgeshire, PE27 3YJ Tel: Fax: Web: This brochure has bee produced by the Marketig Departmet for SIG Roofig. All rights reserved. No copyig by ay meas is permitted, except whe permissio is give i writig by SIG Roofig. This brochure cotais maufacturers' product iformatio that is reproduced by SIG Roofig i good faith, based o the latest kowledge available at the time of goig to prit. Whilst every effort has bee made to esure that the iformatio is curret ad correct, as distributors SIG Roofig caot accept resposibility for the applicatio ad specificatio data featured. Neither ca we accept resposibility where the maufacturers' istructios have ot bee followed. We reserve the right to amed, withdraw or substitute these products at ay time. SLATE/07/2014/VO3 Desiged ad produced by PickerigHutchis.