About the 13w Single-Ended GX23 Base UVC Bulb - BOGOF Manufacturer: UVC Bulbs ADD ONE 13W BULB TO YOUR BASKET AND RECEIVE TWO!!! This 13w bulb has a unique 'double-fin' appearance at the base of the bulb. It is suitable for the Fish Mate 15000 Powerclenz filter. This bulb will not fit PondXpert products.
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