... :nigrescence black,Ni plating,Zn plating 1. Item name: u nut from china2. Material: stainless steel, iron, copper, aluminum, carbon steel3 ... , blue zinc, color zinc, yellow zinc, black zinc, chrome4. Standard: JIS, BS, GB, ISO, DIN, AISI5. Size: all sizes6. The use ... drawings, we can produce high-quality metal for you. u-nut