ANSI Roller Chain is standing on JIS B 1801. The uniqueness includes SBR ( Solid Bushing & Roller) having no seam on bushing and roller which creates outstanding character against initial elongation and wear. Fundamental Structure Outstanding longer wear life Conventional split bushings deform into a barrel shape when side plates are pressed on, leaving only two-point contact area. SBR ( Solid Bushing and Roller) chain has extremely cylindrical inside and outside bushing walls resulting in full contact to disperse bearing pressure. Less pressure ensures excellent wear resistance. Up to 2-3 times longer wear life over curled bushings The curled, split bushings have a seam where tiny space allows lubricant leakage resulting in shorter wear life. SBR has no seam resulting in lower bearing pressure allowing the bushings to retain lubrication resulting in much longer wear life. Relaiable performance SBR is cold-forged from steel rod. Cold-forming process also works with the molecular structure ( grain) of the steel running lenthwise in the bushings thereby increasing gatigue strength as well as preventing bushings from breakage, Hitachi SBR chain improves performance of transmission with minimizing elongation for long period of time.