Ge F13t5 Cool White Fluorescent Bulb 21 In. T5 Mini Bipin G5 13 W 850 Lumens 4100 K 60 Cri Cd 21" long 0.6" diameter T5 with miniature bi-pin (g5) base 4100K cool white light appearance Cool white light perfect for sizable spaces Lasts 2.3 years based on 6 hours per day usage