Brand: CoolShirt Systems
This 7.4v battery fits the Cool Shirt Waist Pack Cooling System (Part No. CS2013), but the 4.4 Ah capacity lasts longer than the original 2.2 Ah battery. This battery is a little larger, so it gets installed in the pouch in front of the pump instead of next to it.
The 7.4v Battery Charger (Part No. CS430) is sold separately.