forging bevel gears 1,material:STEEL(A3/45) 2,industrial gear got ISO 3,8 year sprocket and gear ... ISO, ANSI quality certification. high precision and good wear resistance. 2, surface treatment is black, galvanization, chroming and colored drawing. 3 ... ,material: C45/A3, surface: chroming, heat treatment, standard: ISO,ANSINo.2 Machinery transmission sprocket:16A-18T, material:C45/A3, surface: heat ...