Protection circuit built in so you can't drain the batteries too low or overcharge them. 5000ma for long run times. There are no other 21700 batteries on the market that will give you longer run time in our lights then these. Will work with only our Coyote Cannon Light, 50KAP headlamp and our new 40KAP Headlamp that came out around 5-1-2022. 1 year warranty on Batteries. While these batteries should last around 10 years, we only give a 1 year warranty because we can't control power surges or the batteries accidentally getting shorted or damaged.
