EarthTronics CF13BL1B 13-Watt Spiral Compact T3 Florescent Light Bulb, Blue, 12-Pack Save money and the earth-this bulb only uses 13-Watts of power and outputs the equivalent light of a 60-Watts incandescent bulb Use indoors or out in sheltered applications 10000 hour average rated life means you'll almost never have to change bulbs. Utilizes an advanced electronic ballast so the bulb reaches full brightness quickly 7 year limited warranty based on normal residential usage (3 hours average usage per day/7 days per week)