Circle (4 Pack PLC-18W 835, 4 Pin G24q-2, 18 Watt Double Tube 4 Pack, 5000k
They are also compatible with fixtures using the Panasonic FDS18E35/4 lamp, including WhisperLite fan models FV-08VQL4, FV-11VQL4, FV-15VQL4, FV-11VHL1, FV-08VKL1, FV-08VKSL1, FV-08VKML1, FV-05VFL2, FV-08VFL2, FV-11VFL2, and FV-08VLS1.