Motorola Original PMMN4069 IMPRES Li-ion 1400 mAh Submersible (IP57) Battery - Intrinsically Safe (FM) . The IP57 is a higher rating than the standard IP54 that helps provide first responders with high reliability in emergency situations. The number "5" stands for the dust intrusion rating, or the capcaity to withstand the effects of fine, abrasive dust particles. The "7" means a higher water intrusion rating.
