GE Mod-U-Line 1-5/8 in. Spacing Ecolux 31-Watt 24-in Medium Bi-pin (t8) 3500 K Bright White Ubend Fluorescent Light Bulb (15-Pack) in the Fluorescent Light Bulbs department at Lowes.com
Eiko 13W 1.6" Gap 3500K Hybrid T8 U-Bend LED Bulb | LED13WT8/U1/835-G9DM | Bulbs.com
2 ft. T8 U Shaped Bulb
jimwhen 10 Pack T8 T10 T12 U-Bend Light Fixture,LED U Shaped Bulbs,18W(40W Equivalent),2200LM Super Bright,5000K Daylight,Dual-End Powered,Ballast Bypass,2FT LED U Bent Light Bulb for Office,School - - Amazon.com
Amazon.com: PHILIPS Linear Fluorescent T8 U Bend Lamp, 32 : Tools & Home Improvement