Pack Of 6 F13T5/CW Straight 13 Watt T5 Linear Fluorescent Tube Light Bulb, Cool White, 4100K Super Long Life Light Bulbs (Pack of 6) F13T5/CW 13-Watt T5 Tri-Phosphor Fluorescent bulbs 16 watts Energy Used, 850 lumens Light Output DOUBLE EXTRA LONG LIFE - 20,000 HOUR 4,100K Color Temperature, 60 CRI, 21" Maximum Overall Length