Aquatop UV-9W 9 Watt 110V UV (UVC) Replacement Bulb G23 for UVE9 CF400 CF500 UVCP-9 compatible with AquaTop models: UVE9 Submersible 9 Watt UV Sterilizer, CF400 Canister Filter UV Sterilizer, CF500 Canister Filter UV Sterilizer, UVCP-9 Submersible UV Sterilizer Used in 9 Watt UV G23 base sterilizers Base: G23 Bi-Pin - Life: 10,000hrs Super Life