From Manufacturer
This B&H kit consists of two Watson Pro Buddy System High-Load V-Mount Batteries and a Watson Pro Quad Position Li-Ion Battery Charger. This kit has been assembled to provide you with four high-capacity batteries that can be carried on a plane, and a two-bay charger. Each battery splits in half for airline travel and supports a 15A draw when recombined. Each battery supports 15A maximum load, which allows it to support cinema cameras rigged with accessories, large LED lights, or other gear that uses a V-mount.
SMBUS communication is enabled through the V-mount connection and enables RED DSMC2 cameras to display detailed battery info in the viewfinder. The charger supports charging four batteries simultaneously at 2.5A per battery. The charger can be used to charge batteries or provide power over its XLR connector, but not both at the same time.