MIFAB® SUPER-500-O gravity oil interceptor with 500 U.S. gallons of liquid holding capacity has a limited lifetime warranty and is made in the U.S.A. out of seamless, rotationally molded High Density Polyethylene with 3/8” uniform wall thickness. Interceptor is designed for above or below ground installation and includes an adjustable lid system, sample port access, deep seal trap covered by lid, internal air relief by-pass, adjustable oil drawoff assembly (1 1/2″ I.P.S.) on each side, double vent connections (3″ I.P.S.) on each side, stainless steel calibrated orifice plate (internal flow control), base for support and floor level installation and 4″ no hub inlet and outlet connections. Composite lids provide a water / gas tight seal and have a minimum of 20,000 LB. load capacity – in accordance with the loading requirements of AASHTO H20. The high density polyethylene material is PE 3135 from Dow 9.39 with a density of 0.939 g/cm3. For indoor/outdoor use.