New Ratech pinion depth setting tool.  This tool makes ring and pinion installations alot easier.  Tool is axle specific, and allows you to take a measurement with the pinion installed and compare to the depth marked on a new pinion.  The difference is the shim requirement.  Tool mounts on pinion and carrier bearing hole. This tool is for GM 7.5" & 7.625" 10-Bolt differentials.