Malkoff Devices P60 style Drop-in LED Conversion with solid brass heatsink construction. The output is approximately 425 measured out the front lumens. The current draw is only 800ma at 6 volts. The full output runtime is approximately 1.25 hours on two CR123 primary batteries with a nice long taper as voltage drops. It will easily illuminate objects at 350+ feet and will blind opponents within a 100 foot radius. The LED is a Cool White (6200K) Cree XP-G2. This design utilizes a custom orange peel reflector designed by Don McLeish. The reflector offers a very nice balance between throw and spill. It is an outstanding room lighter and short to medium spotter. Designed for rugged service from the ground up. It is fully potted to stand up to rough service and recoil. This item is covered by Our Lifetime Warranty. Things to Know Before Purchase: The M61 will work in the Surefire M951, but do to variations over the production lifetime (of the 951) there are a few caveats. If you need help with the installation, please feel free to give us a call. The M61 will not work in SureFire Forends. Please see our SureFire Forend specific models. This dropin was designed to operate at maximum output for extended times in metal lights. Operating the unit for more than 15 continuous minutes on high in plastic lights may damage the dropin. This is not an issue in metal lights or plastic lights with a metal head. WARNING: This light is capable of causing eye damage at close range. Please use the light responsibly!!! Made in the USA. Some parts not domestically sourced.