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
Feit Electric 30-Watt 9 in. T9 G10q Linear Circline Fluorescent Tube Light Bulb, Cool White 4100K (1-Bulb) FC30/CW - The Home Depot
Led Lamp Circular Fluorescent | Led Circular Fluorescent Tube - T9 Led 205mm 375mm - Aliexpress
Feit Electric® 32W 12" Circline Cool White Fluorescent Light Bulb at Menards®