MIFAB® BIG-O Series HDPE rotational molded oil interceptor. Unit shall include: 3/8” uniform wall thickness, deep seal trap covered by lid, adjustable lid system, stainless steel calibrated orifice plate (internal flow control), internal air relief by-pass, adjustable oil draw-off assembly (1 1/2″) on each side, double vent connections (3″) on each side, sample port access and 4″ no hub inlet and outlet connections. Composite lids provides a water / gas tight seal and has a minimum of 20,000 lbs. load capacity. The lid is designed in accordance with the loading requirements of AASHTO H20.