For use with MW heavy duty housing ends (p/n 58595, 58598, and 58599). Includes 5/16" thick 7075 aluminum caliper mounting brackets, aluminum brake hats that are drilled to accept 5/8" drive studs, slot-drive rotor attachment system, all required mounting hardware, and MW 4 piston calipers with linings. Saves up to 10 lbs of rotating weight. Installation - Service instructions can be found on Service Bulletin #0035 and #0086.