Lees Undergravel Knockout Plugs 4 Pack
Lees Uplift tube knockout plugs. Fits Lees under-gravel filters. Great for when you switch from an air pump to a power head, or any time you need to remove an uplift tube from your filter plate. Pack of 4 plugs for uplift tube holes.
The OD of the plug is 1 1/8". This is without opening the manufacturer's packaging.