Hayward SP1048AVH Suction Outlet Drain Bumper Adapter For Hayward AV Drain Suction outlet bumper adapter Designed for concrete or vinyl and fiberglass pools Fits Hayward 8" round main drain/suction outlet covers 2008 and prior (2007 and prior which are Anti-vortex "AV" only) Prevents automatic pool vacuums from becoming stuck on the main drain Does not fit VGB Compliant round main drain/suction outlet covers.