Whenever you have removed the rear wheel of your motorcycle, you need to re-align the chain or belt. This handy tool really takes the guesswork out of this job. By simply putting the Chain Alignment Tool on your sprocket or pulley, the laser beam indicates if everything is lined up properly. Correct alignment increases the lifetime of your complete drive train, tire, and wheel bearings, reduces fuel consumption and improves road holding. This Class-2 quality laser features a tolerance of less than 0.01mm per meter chain or belt and comes complete with three AG5 batteries. The Chain Alignment Tool is Made in Germany and economically priced-every bike owner should have one in his toolbox. It definitely is a must for professional workshops.