transmission sprocket 1,Metarial: C45/A3 2,High precision without sharp edge 3.Certificate:ISO,ANSI,DIN 4.Hard surface/teeth ANSI C45 roller chain hard teeth transmission sprocket Feature 1, all made by advanced CNC lathe, pass ISO, ANSI,DIN quality certification. high precision and good wear resistance. 2, surface treatment is black, galvanization, chroming and colored drawing. 3, material is A3 ...