Product description: Combination Slab on Ground (SOG) bar chairs are designed to support reinforcing mesh/bar in slab-on-ground projects. They are manufactured to provide dual-height options in the one bar chair size for increased application flexibility.  As they are manufactured from plastic there is zero-risk of rust problems and their lightweight and stackable design makes handling easy.  A standard flat base on the chairs minimises penetration through plastic and a wider base with no-slip pins is available for purchase separately when extra stability in sand or similar is required.