Rotationally-molded polyethylene with a Pedestrian-rated bolted composite cover. Includes Slick Stick Monitoring System CAPACITIES Total - 57 gal. / 7.6 cu. ft. Oil - 14.25 gal. Sand - 7 gal. DIMENSIONS - L x W x H 37" x 28" x 28-1/2" Weight 93 lbs. Inlet & Outlet 4" plain end Vents 3" plain end