Description: LSK washer Ø 60 mm is used for attachment of light insulation panels e.g. to wall. Y40-PA Ø 40 mm black polyamide (nylon) washer fastens, for example, single-ply roof covering to fix-layer of concrete or wood. Y40-PP Ø 40 mm washer fastens insulating or acoustic panels. ZN washer is made of galvanized sheet metal.