The Primitive Racing Rear Differential Skid Plate protects the rear differential housing on the Subaru WRX and STI from rock strikes and trail debris. WRX and STI use different rear differentials despite sharing a chassis, WRX runs the smaller R160 housing while STI runs the larger R180, so this listing carries cover styles for both: a bolt-on Mini plate and a thicker Standard cover for the early WRX, a 5-Bolt Uni cover and the newer Uni Plus Side Drain cover for later WRX generations, and matching R180 Mini and Uni covers sized specifically for STI. Select your exact model and year range from the Model menu below, WRX and STI options are listed separately since the covers are not interchangeable. Canada-wide shipping from Flat 4 Offroad in Calgary.