Ge lu150/med/ltp. it's a 150 watt, cl glass ed17 high pressure sodium bulb with a medium base. the bulb provides 16000 lumens and has a color temperature: 2000 kelvins. with a cri: 22, and an mol: 5.43. the bulb is non-dimmable, with a rated life of 24000 hours. item notes: for use with s55 ballasts.