A Grade 8.8 Nylon Lock Nut, also known as a Nyloc nut, is a type of self-locking nut designed to prevent loosening due to vibration. It features a nylon or polymer insert that deforms elastically when a bolt is inserted, creating friction and preventing the nut from rotating off. These nuts are commonly made from medium-carbon steel and are typically zinc-plated for corrosion resistance.