13 Watt Spiral Lamp Blue Compact Fluorescent 13 watt spiral lamp blue ,120 volts with a medium(edison) screw base. Small size easily replaces standard incandescent light bulbs. 75% energy savings compared to a 60 watt bulb. 10,000 hrs. average rated life. Electronic ballast provides instant on, no flicker. Low mercury. Not for use on dimming circuits, timers or remotes. UL approved and CUL listed.