The Efest rechargeable battery features a flat-top design.

Safe chemistry LiMN minimizes the risk of venting with flame or explosion. IMR-safe chemistry batteries do not include added or built-in protection circuitry, resulting in a slightly shorter battery length for compatibility with most mods. To preserve longevity, avoid discharging the battery below 2.5V.

Please be aware that IMR cells lack built-in protection circuitry due to their inherent safety, and discharging them below 2.5 volts can diminish cycle life and performance. The maximum charge voltage is 4.25 volts.