This is an authentic Craftsman replacement part, sourced from the original manufacturer for use with air compressors. The hex head screw is used to secure the motor assembly to the bracket on the tank of the compressor. These screws are sold in packs of eight pieces and the packs are sold individually.
This is sold as a set that contains eight washers. These parts attach to the tank and are made out of metal. They are genuine items that are supplied by the original equipment manufacturer for use with Craftsman air compressors. During replacement, it may require a wrench to help install these parts correctly. They will require replacing if they become bent or broken.