Name: nylon expansion bolt 1.Material: plastic 2.Finish: white, grey 3.Advantage: wont shred, split, crack Concrete, lightweight concrete, sand-lime bricks, solid red bricks, pumice solid bricks, solid gypsum, natural stone etc.The ideal fixing for infinitely variable adjustment of timber substructures. The the top of the plug is flush with the surface of the batten to the wall can then be ...