Main structure and door bars are 1-3/4" x .095 D.O.M. tubing. Internal bracing is 1-3/4" x .065 D.O.M.. It is built for 45" to 48" roof height with right side door X standard. 1/8" thick hot roll steel is used for the floor pan, pedal plate and left side rocker/weight tray. The three main frame rails are made of 2" x 3" x 11 ga. It will accept nearly any front frame section, but only our tail sections will fit directly to it.