Dana Spicer shim 720.06.042.02 or 7200604202 is a genuine part for off highway axle applications. A shim is a thin precision spacer used to set where the ring gear and pinion sit, which decides how the gear teeth mesh and how much lash they run with. Shims at the carrier bearings are also used to bring those bearings to the right preload so the carrier stays put under load. When shim thickness is off, it shows up as a tooth contact pattern that sits too deep or too far toward one end of the teeth, or as lash that is too loose or too tight. Call us to confirm proper fit for your axle.FeaturesDana Spicer shim 720.06.042.02 or 7200604202For off highway axle applicationsGenuine Dana Spicer part sold by Pro Gear and TransmissionShims set ring gear and pinion position, which controls tooth mesh and lashShims at the carrier bearings are used to set bearing preload