Carriage Bolt, Round Head Square Neck Bolt 1) Standards: DIN603, ISO8677, ANSI/ASME B18.5, GB12, GB14 2) Material: Carbon steel 3) Finished: Plain, Zinc, Black, Nickel, H. D. G. 4) Diameter: M6-M20 5) Packing: G. W.: 25Kgs/Carton or small box packing or according to customers' favor 6) Delivery: By sea 7) Payment term: T/T, L/C at sight