BF-190 "U" shaped, 40 watt Replacement Bulb for the current BK-40 Flowtron Bug Zapper, which is the BK-40D. Bug Zapper bulbs should be replaced every season to ensure maximum output in the invisible ultraviolent frequency range. The BF-190 has replaced the discontinued BF-50.
Check our Replacement Bulb Page to ensure the correct replacement bulb for your bug zapper. If you do not see your make/model listed on that page, then sorry, we are unable to advise a bulb for your unit.