Loop-Loc Ultra-Loc III Solid Safety Cover w/ Pump - 18' x 36' Rectangle w/ 2' Offset 4' x 8' Right Step aqua-king-king-shark-2-2-plus-commander-swivel-assemblies Outer Diameter is 10 7/8"

Outer Diameter is 10 7/8" and Inner Diameter is 7"

Manufacturer Part # R0529400

Manufacturer Part # B663 More Info We highly recommend also changing the pump seal with a new motor

Manufacturer Part # 817-0106

Manufacturer Part # V38-131

Loop-Loc Ultra-Loc III Solid Safety Cover w/ Pump - 18' x 36' Rectangle w/ 2' Offset 4' x 8' Right Step aqua-king-king-shark-2-2-plus-commander-swivel-assemblies Outer Diameter is 10 7/8"Exclusively From LOOP LOC: The Ultra Loc III Solid Safety Cover Is Tougher than Tough, Stronger than Strong! You no longer have to choose between the light weight of a mesh pool cover and the light blocking benefits of a solid cover. The revolutionary Ultra Loc III gives you the best of both worlds! Premium coated vinyl material with enhanced 100% polyester Rip Stop Scrim. Bounces back better and drains super fast. No more ugly pockets of water and