Chassis Engineering offers more Aluminum/Steel wheel tubs than anyone. Chose from aluminum or steel versions of many different sizes. These tubs will work with either 2 x 3 or round tube rear frame rail kits. Tubs are shipped in a flat box, saving on freight costs over pre-assmembled or carbon fiber tubs. Half moons are cut and edges rolled, flats are pittsburgh seamed for tight and precise assembly. (pr.)