IMPRES™ Li-Ion Rechargable Battery, 3200mAh, IP68, TIA4950 (PMNN4810) TIA4950-certified & high capacity The TIA4950 battery is TIA4950-certified as intrinsically safe. When used with IMPRES chargers, the charge cycle increases by 43% to increase talk time. The self-calibration feature eliminates having to recondition the battery every 29 days.