At verges and side abutments, half slates must be used in alternate courses. Please note the half slates are sold in pairs, 1x left handed and 1x right handed half slate. With its thin leading edge and hidden lock, provides a cost-effective roofing solution where an authentic slate appearance is called for. Replacing Redland's iconic range of thin leading edge slates was never going to be easy, the Richmond, Saxon and Landmark Slates were the first of a new breed of concrete slates when Richmond was launched 30 years ago. Properties Nail size: 45mm x 3mm - aluminium alloy. 45mm x 3.35mm - stainless steel ring-shank. Slate finish: smooth - through coloured & acrylic coated. Certification BBA certified. 2nd generation performance Richmond 10 is the epitomy of a cost effective roofing solution where an authentic slate appearance is called for. Its unique design offers a thin leading edge and hidden interlock without compromising strength, durability and weathertightness. Completely redesigned to incorporate the latest concrete tile technology, Richmond 10, along with the other variants in the thin leading edge range (Saxon 10, Landmark 10 and MockBond Richmond 10) offers the specifier an elegant solution to all roof designs down to a pitches as low as 17.5. Now offering a 10 slates/m solution and a unique single annular ring-shank fixing, Richmond 10 Slates are even quicker and easier to lay than their predecessors. Although the classic Slate Grey colour continues, the new range has been enhanced with new Flame Red and Rustic Brown variants, plus two intense Black and Blue variations, all designed to give an authentic slate appearance in addition to the thin leading edge design.