machine screw : 1.size:M4*13.8 2.Finish:Ni-plated 3.material:carbon steel 22A machine screw:Features for this item:1. material: carbon steel 22A2. size:M4*13.83.head: cheese phillips4.function:to connect the electric partsFeatures for all our products:1.Standard: GB BSW, JIS, ANSI,DIN, Non-standard2.Material: carbon steel alloy steel,aluminum3.Finish: white/yellow/blue/black zinc,nickle,black ...