Superior Control: Experience superior control and functionality which are perfect replacements for your worn out or rusty hubs; they are waterproof so worry free for your vehicle Full Potential: Upgrade confidently and unlock your vehicle's full potential; full dial-turn for secure engagement/disengagement Enhance Performance: Enhance your vehicle's performance with the 423 Hubs conversion kit; changed automatic to manual-nut kit may be required Material: It is built to exacting standards, they feature patented technology and smooth operation for the performance that you expect and need; these hubs are made by die-casting aluminum into pre-made stainless jackets for the ultimate combination of light weight and corrosion resistance Vehicle Compatibility: This fits your 1974-1977 J20 Pickup (6 Bolt 19-Spline), 1960-1977 3/4T (K-20) Pickup, 1957-1968 1/2T W-100 P/U (6 bolt 19-spline), 1963-1977 3/4 Ton W/3500 Axle ex. F/T & 1956-1975 3/4 Ton Pickup, Travel-all 3/4 Ton