Product name: Hex washer double thread self tapping screw Specification: 6x50 Packing: We pack Hex self tapping screw accoring to our customers' request Standard: ANSI, ISO, DIN, BS, JIS, AS Material: Low carbon steel( C1018, C1022), Surface: Zinc plated(yellow, black, green), black oxide, nickel plated, chrome plated, Cr+3, hot dip galvanized, brass plated