ASP Lithium-Ion rechargeable batteries are custom-fabricated to provide increased energy density and longer life. Our 21700 battery is optimized for use in high-drain devices such as our performance flashlights, and features a Protection Circuit Module (PCM)—an important safety feature that guards against overcharging or over-discharging.

Our latest generation of Lithium-Ion batteries feature an integrated USB-C charge port. This means that in addition to in-light recharging (with compatible ASP flashlights), the battery can be charged on its own, simply by plugging a USB-C cord directly into the cell. We recommend our Retractable cords (sold separately), or any common, quality USB-C charge cord may be used.

IMPORTANT: This battery is designed exclusively for use in ASP tactical flashlights (and conversely, ASP Lithium-ion batteries are the only rechargeable batteries that should be used in our lights). It features a proprietary terminal design that eliminates the risk of inadvertently sending recharging power through a non-rechargeable battery, and therefore may be incompatible with non-ASP products.

The 21700 includes a Link Case, to safely store, protect and transport the battery. It features an interlocking design that allows multiple Link Cases to be connected to one another for efficient organization.

IMPORTANT: Separately-packaged batteries (meaning any batteries not shipped packaged with a flashlight) can not be shipped via US Mail, or by air (UPS overnight, 2-Day, etc.). If you order these batteries, please make sure to only select standard UPS Ground shipping.

ALL flashlights and/or batteries cannot go UPS Ground to Alaska, Hawaii, Puerto Rico, US Virgin Islands or Channel Islands off the shores of California.