Cold rolled steel construction w/ black powder coat finish. Axle mount plate is 1/4" steel with TIG welded fabrication. Engineered gusset design is stronger then any on the market. Will fit 3/4", 20MM and 1" axles in one kit! No need to choose your axle size Fits all No School 1928-1936 Duolamp tail lights, and Biltwell Lights Mounts to left side axle. (Drivers left) -Perfect for your Chopper or your stock motorcycle. These do not fit sportsters as the axle is too close to the shock mount. The appropriate bracket would be the shock mount bracket I sell.