Sunlite 00787-su sl13/gu24/41k 13w gu24 spiral cfl light bulb, gu24 base, cool white sunlite gu24 spiral compact fluorescent lamps fit into most energy efficient gu24 fixtures and give off a cool white light much like a 60 watt incandescent bulb. These energy efficient cfl lamps can last up to 7.3 years with normal household use of 3 hours a day. This energy saving 13 watt 4100k, gu24 base bulb offers 900 lumens of light output and has an average rated life of 10,000 hours.