The Nitecore HLB-1300 1300mAh rechargeable Li-ion battery pack is designed specifically for the Nitecore UT27 headlamp. At 4.81 Wh, this small catridge can power the UT27's spotlight for up to 10 hours on low and reach up to 520 lumens on Turbo.

The Nitcore HLB-1300 Li-ion Battery pack is 3.7V and can be fully recharged within 1h and 50 minutes. Red and green indicator lights are built into the battery for a real-time charge status.