A nut is a type of fastener with a threaded hole. Nuts are almost always used in conjunction with a mating bolt to fasten multiple parts together. The two partners are kept together by a combination of their threads friction with slight elastic deformation, a slight stretching of the bolt, and compression of the parts to be held together. Specifications. Height 0.6 in.. Width 2.3 in.. Length 2.3 in.