bolts and nuts 1.experienced manufacturer 2.high qulity material 3.we can do it as ... main manufacture bases, 5 main factories with 12 product lines of machining, welding, heat treatment, assembly, painting, casting ect., ... 1)Grade: 4.8 -- 12.9,A2, A4(2)Size: M3-M72(3)Finish:plain, zinc plated, hot dip ... export packing or According to customer's requirement high quality sorts of plow bolts and hex nuts