Solray SR-6012 F39T5/841 39 Watt T5 4100K Fluorescent Tube Cool White Light Bulb 10 Pack Sold in a pack of 10 bulbs. 39 watt fluorescent light bulbs. Color Temperature: 4100K - cool white light. T5 bulb with a 46 inch length. Has a double extra long life of 20,000 hours.