Project 'Green' House #1: LED replacement lighting for circular fluorescent tubes // DavidJB.com // Python, Technology, Web, Linux, and more, by David Beitey
FC8T9/CW Circular Fluorescent Light Bulb, 8 Inch Circline T9 22W Lamp Tube for r | eBay
Feit Electric® 32W 12" Circline Cool White Fluorescent Light Bulb at Menards®
AMATRON ETL Listed 16" T9 24W LED Circline Bulb LED Circular Tube 5000K Daylight Frosted Lens with Non-Dimmable External Power Driver to Replace 16 inch 40W Fluorescent Circline - Led Household Light