A and B series roller chains: 1.Materials: 40Mn 2.Color: Dark ... 12B,16B,...48B 35,40,50,60,80...240 roller chains :25,35,41,40,50,60,80, ... 56B,64B,72Broller chains,transmission chains,industrial chainsdriving chain,heavy duty chain:1advanced technology, advanced equipment2high technical capabilities3employ experienced technical ... service9)Mutual development,mutual benefits. 06B-3R triplex roller chain