13 Watt Spiral CFL bulb is a 60 Watt equivalent incandescent replacement that offers over 75% energy savings. This 2700k CFL bulb is rated to last 12,000 hours that eliminates 818 lbs. of CO² from being released into the air and provides $56 in electrical cost savings (at $0.10kwh). The soft white CFL is the standard color which has an electronic ballast providing an instant on, no flicker starting. Medium screw base.