Metallics Domestic cap screw has 18-8 stainless steel construction for added strength and durability. This screw has hex head of size 0.428 - 0.438-Inch x 0.15 - 0.163-Inch. The 1-Inch screw has 1/4-20 UNC thread. It is suitable for electrical, plumbing, heating and air conditioning industries. Cap screw is RoHS Compliant.