This tool is specifically designed to be used with the ICM SpecMiata alignment system. This tool dramatically reduces the amount of time required to perform an alignment. Constructed from 1/4" aluminum for durability. No longer is it necessary to repeatedly measure each side of the wheel to determine the toe. Simply hold this tool up against the edge of the rim and it is very apparent if the wheel is toed in our out. This tool is NOT adjustable and will only work on 15" rims with the ICM String System. This tool will work with other string systems as long as the clearance from the wheel to the string is less than 2.5" and the wheel diameter is 15".