quick coupling 1.material: plastic and steel 2.different types 3.straight,bend,cross 4.two holes,three holes and etc. quick coupling1.material: plastic and steel2.different types 3.straight,bend,cross4.two holes,three holes and etc.we are mainly engaging in heavy-duty trucks' parts,like HOWO ,STYER and some parts ofBenz,volvo,scania,man & etc.We also produce many parts for tractorscustom-made ...