Inova T2TMB-HB T2 Lithium Powered LED Flashlight Light output on High is 245 lumens and on Low is 22 lumens Run time on High is 3 hours 25 minutes and on Low is 34 hours Effective range is up to 475 -Feet or 145 m Mineral Glass optical window has double-sided AR-coating and Teflon seal to withstand environmental pressures High-powered energy efficient 50,000 hour LED