... 1.The service life of O-Ring or X-Ring Chain is greatly depended on the wearing ... shaft and the sleeve. The "O" ring or “X” ring will greatly reduce the wearing and thus prolongthe ... 530V, 530VM, 630V, 630VM,428V-X,428VM-X,520V-X,525V-X,530V-X,530VM-X,630V-X,630VM-X,420HZ,428HZ,520NZ,525HZ,530HZ,630HT3 ... 9.The sealing performance of X-ring is better than O-ring. O-ring X-ring racing ATV motorcycle chain