Luxrite LR20761 (4-PACK) F17T8/735 17-Watt 2 FT T8 Fluorescent Tube Light Bulb, Natural 3500K, 1350 Lumens, G13 Medium Bi-Pin Base Color/Finish: Natural Color Temperature: 3,500K Average Lifetime: 13,000 hours Lumens (light output): 1350 G13 medium bi-pin base