... , BS, ISO2. Size: M6-M303. Grade: 3.6, 4.6, 4.8, 5.6, 5.8, etc. 4. Material: carbon steel, alloy steel, stainless ... steel, etc. 5. Surface: plain, zinc plated (yellow, blue, white ... and blue), black, HDG, etc.6. Length: 10mm-300mm Hex bolt zinc plated low price