High technique requirements O-Ring Roller Chain:35,40,50,60,80,100,06B ... service life of O-Ring Chain is greatly depended on the wearing between the pin-shaftand the sleeve. The ... service life by 5 times. It is especially suitable for the adverse environmentssuch as the one bearing water, mud ... ring chain be recommend the no. 1 in Chinese chain association, berecommend to worldwide.1) Model: 35,40,50,60 ...