"Because there is no such thing as having too many backup options on the street, ASP has introduced its first triple-fuel flashlights; the Sentinel e3 and Sentinel X e3. These lights ship with a 16340 lithium-ion battery that recharges inside the light, providing a potent 400 lumens of output. If you don’t have the time or place to recharge, just swap out the rechargeable battery for a CR123A disposable cell. No CR123? No problem—you can also put in a common AA battery in a pinch, with no special adapter needed."