1. Size: M4-M52, 3/16"-2" 2. Length: 30mm-3000mm 3. Class: 4.8,5.8,8.8,12.8 1) Standards: B7 B8 B8M DIN 975, DIN ... 976A, , UNC ROD, BSW ROD2) Size : M3-M56 ... steel, low carbon steel, carbon steel, alloy steel4) Grade: 4.8,5.8,8,8.8,12.85) Surface: Plain, Black, Zinc Cr+3,Yellow Zin ...