OEM Motorola NNTN7335  IMPRES high-capacity 2800 mAh,  Li-Ion battery.  IP67 Rated.  

Compatibile with XTS 2500, XTS 1500, MT1500 and PR1500 portables.

IMPRES batteries when used with an IMPRES charger provide automatic, adaptive reconditioning, end-of-life display, and other advanced features. Data is stored in the battery and communicated to the charger via a unique IMPRES communication protocol which is designed to maximize talk-time and optimize battery cycle life — all automatically.