Consists of small (outer) bearing 3/4" cone diameter, large (inner) bearing 1-1/4" cone diameter, waterproof rubber seal and seal retaining ring. RTM carry a comprehensive range of wheel bearings, seals and bearing protectors for the popular Australian-made caravans, box trailers and boat trailers. We carry these products in two brands, AL-KO, a respected German supplier of quality trailer components, and ARK, an Australian supplier of 4WD accessories and trailer components. They are both well respected suppliers.Changing crook bearings is easy and very satisfying that you have done it yourself. All bearing kits fit 39mm round and 40mm square trailer axles.Includes split pin for trailer axle. Does one wheel only.