Chain Alignment Tool Rieju MRT 50 Pro Cross 09-13 The laser light is visible in a line along the entire length of the chain and enables simple and quick visualization. The SE-CAT-Line is ingeniously suited for this application, as both belt markings can be illuminated simultaneously, making it visible whether the rear wheel axle is correctly positioned. Application errors are virtually eliminated. The chain alignment is set in seconds with the help of the precise test device. All that needs to be checked is whether the light line illuminates the same distance from the edge of the chain over the entire chain length.The precisely adjusted rear wheel ensures optimum driving behavior.