1.Finish: plain, zinc, blank and HDG 2.Thread: MM, UNC, UNF and BSW 3.Grades: 4.8, 5.8, 6.8, 8.8, 9.8, 10.9 and 12.9 Carriage bolts DIN6031)Various kinds of bolts available2)Material:carbon steel, stailess steel3)Diameter: 5 to 20mm (1/4 to 3/4-inch) Length: 8 to 200mm (5/16 to 8-inch)4)Thread: MM, UNC, UNF and BSW5)Can be made with different tensile strength, such as Class 4.6, 4.8, 5.6, 5.8,6.8 ...