About the 55w Single-Ended UVC Bulb - BOGOF Manufacturer: UVC Bulbs ADD ONE 55W BULB TO YOUR BASKET AND RECEIVE TWO!!! This 55w bulb has one terminal connector and is suitable for the following products FiltersOase Filtoclear 30000PondXpert SpinClean 40000PondXpert SpinClean Auto 40000Velda Clear Control 100 UVCsOase Bitron 55Oase Bitron 110PondXpert Greenstop 40000 55wPondXpert GreenStop Pro 55wWILL NOT FIT THE HOZELOCK VORTON 55W UVC