The Hi-Tech Lamps part number CF23CLT4100-U is a 23 watt (23W) coiled compact fluorescent lamp made by Ushio.This lamp has maximum overall length of 124mm and a diameter of 53mm The average lifetime is 10000 hours with a much longer typical lifetime in commercial environments. This lamp has a cool white color temperature of 4100 Kelvin (4100K), and has an output of approximately 1600 lumens (1600 lm). This lamp is also known as Ushio CF23CLT/4100/E26 and 3000555. This 23W CFL is an ENERGY STAR?? Qualified Product.