Ronstan's Welded Eye Bolts are made of grade 316 stainless steel and come with a nut and washers. RF159 has a 1/4 in. (6mm) thread with a 1 1/2 in. (38mm) length. It has an aperture of 15/32 in. (12mm) and an overall length of 3 3/16 in. (81mm).