About the 20w Laguna Single-Ended UVC Bulb - BOGOF Manufacturer: UVC Bulbs ADD ONE 20W BULB TO YOUR BASKET AND RECEIVE TWO!!! This single-ended bulb fits the Laguna 8000 Pressure-Flo filter. Please note that Laguna do not supply a 20w UVC bulb anymore as it has been replaced by this 18w version. This bulb is particularly unique as it is both single-ended and single-tubed, with all 4 pins on one end.