Swimming Pool Filter Plug - 16 Pack. These plugs are used for pool that take 1.25 inch diameter hoses that do not have plunger valves to stop the water during filter change. Fits 16' and below above ground pools. It is used to replace the filter pump, and hold back the water while cleaning pump filter. Wall Plug Replacement above ground swimming pool filter pump. When you cleaning the pump filter, put the hole plug to block the pool wall hole tightly to prevent water from overflowing, and the installation is finished. Summer Escape swimming pools that do not have plunger valves so you can replace the filters in the pumps. it is waterproof, chill-proof, small and easy to store, and at the same time has good ductility and expansion. Summer Escape swimming pools that do not have plunger valves so you can replace the filters in the pumps. it is waterproof, chill-proof, small and easy to store, and at the same time has good ductility and expansion. Material: colour: black Package Contents: 16 x Pool Strainer Wall Plugs Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.