Galvanized steel enclosure. Single phase, 3 wire, insulated/bondable split neutral, 30 (1") spaces, 40 poles, 120/240 volt. Main breaker type BW at 25,000 AIC. Ground bar kit (necessary for sub-feeding) sold separately. Tin plated aluminum bus bar. Twin neutral with non removable cross bus. When bonded, unused neutral connections may be used for equipment ground protectors in service entrance application. #2 - 300 kcmil wire range. Electrostatic powder coat, baked urethane painted. Rotates 180 degrees for bottom feed; orientation of main breaker handle consistent with NEC 240-81 requirements because it operates horizontally. G1 box - 14-5/16" width x 34-1/8" height x 3-7/8" depth. UL Listed file E52977.