X-Ring Motorcycle Chain: 428, 428H, 520, 520H, 525, 525H, 530, ... Big Power Motorcycle 1.The service life of O-Ring or X-Ring Chain is greatly depended on the wearing between ... the pin-shaft and the sleeve. The "O" ring or “X” ring will greatly reduce the wearing and thus prolongthe service ... grease is made in USA.6.O-ring and X-ring are made in Tianwan. X-ring racing motorcycle chain 428X,420X,520X,530X ...