These replacement ultraviolet 'blacklight' lamps are compatible with Swan bug killers requiring part number F8 T5 BL368. Such as insect zappers Swan 16 watt SK80, SK90 Vermatik FuturaZ16, Vermatik Rapidzap 16W ACV16 or other Vermatik 16W fly zappers. They will also work in other brands of fly zapper that take 300mm 8W UV bulbs