They are assembled with the same rivets used to attach kins on airplane wings! A Liberator Convertible is made stronger and lasts longer than any other truck in the industry -- Guaranteed! * Five Crossbars on the Senior with a logo channel and four crossbars on the Junior with a logo channel for more frame support. Additionally, this helps prevent smaller boxes from falling through. * One-piece, heavy-gauge steel lock bar prevents premature wearing. * Wheel brackets are constructed of non-cracking, high-strength extruded aluminum. * Two-Year warranty and a lifetime warranty on the axle brackets!