1 set (4) per mill.
Batteries we sell are rechargeable NiMH (Nickel Metal Hydride) low self discharge, 2000 mAh AA. NiMH batteries advantages are there is no memory issue (you don’t have to fully discharge before recharging as Nicad batteries) and recharging cycles are rated 400 cycles. Also not toxic when disposed of. Low self discharge- means the batteries will stay charged much longer when not in use compared to standard NiMH batteries. 2000 mAh (milliAmpere hour) is the capacity of the battery. How much energy it holds.