7.4V 5200mAh Li-Ion Battery with built in 4 level controller, Digital Display & temperature control, for use with the 7.4V Base Layer, Socks, Glove Liners or Gloves. This battery will not work in line with a heat-troller. If you need a battery to do that then order Item Number 27760050
This is only the battery. If you do not have the charger, then you need to order that also!