... needLife Time:10 Years Buying tipsThe most popular, the low speed, small power, can choose the A3steel Carburizing, quenching,tempering ... 630 A style and B style roller chain:RS series,RO series,RF series silent chain:SC3(CL06),Pitch is 9. ... , Plating bake proces, Black turn grinding process Chain modelPitch(mm)Roller sdiameterWidth between inner platesPin diameterInner plate depthUltimate tensile ...