These housing ends are CNC machined from alloy billet steel. They are for race use and have threaded holes for easy installation of caliper mounting bracket or backing plate. Specifically designed to fit the Strange A1022 non-adjustable bearing with Spiro lox and retainer plate. They are 1.125" wide with a 2.875" diameter axle bearing bore. The bolt pattern is 5 holes on 3.375" bolt circle. The bolt holes are 3/8" diameter. Kit contains a pair of housing ends.