To finish up the housing and strengthen it internally we installed LPW's Ultimate Cover. The two studs contact the backs of the main caps inside, keeping them from flexing during extreme conditions such as racing. If the caps don't flex, the tolerances inside stay tight on the launch and your rear end lives. The extra holes on the edges of the cover's bracing are in case you'd like to install LPW's Axle Tube Brace(TM). This device benefits by stopping forward movement of the housing tube ends and eliminates case distortion.