Trail King Industries. Advantage series bottom dump trailers hold 22 cu yd and are 39 - 42-ft long. Full-width aluminum fenders are sloped to effectively shed material. The one-piece design of the hopper and frame provides strength and weight savings, while lightweight cross-braces tie the frame together to minimize flexing and twisting. Additional features include pin-style landing legs, aluminum windrow deflectors, and rear manual control.