F13T5CW – T5 21 Inch Under Counter Fluorescent Bulbs Cool White 4100K 13-Watt F13T5/CW 21” CW Long Life Replacement Tubes for Under Cabinet Lights – Pack of 6 Bulbs - Amazon.com
Bluex Bulbs 4 Pack T5 21 Inch LED F13T5CW LED Replacement Bulb F13T5 LED 9 Watts 920 Lumens Cool White 4100k F13 T5 13 Watt Bulb - Amazon.com
x5 Bell 21" 13w T5 Fluorescent Tube - Cool White / 4000k (840) - 5412 | eBay
Satco 13W T5 21 Inch Soft White 2 Pin Fluorescent Tube Light Bulb - FLO10025 at Batteries Plus
4 Pack of 8W/21" T5 LED Tubes Replace 13W Fluorescent Tube for Undercabinet Lights Directly to get Over 50% Energy Saving and 50K Hours Life - Amazon.com