Hex Nylon Insert Lock Nut Kit, 410 piece(s), Nylon, Steel material, including a(n) 6-32 Hex Nylon Insert Lock Nut and 5/16-18 in. Hex Nylon Insert Lock Nut and 10-32 Hex Nylon Insert Lock Nut and (20) 3/8-16 Hex Nylon Insert Lock Nut and 1/4-20 in. Hex Nylon Insert Lock Nut and 8-32 Hex Nylon Insert