The BMHL Large Battery provides 450 flashes at 200ws with a Four Year pro-rate warranty. It uses three decks of high amp hour NiMh battery cells and is about 3 inches tall and weighs just over four pounds.
The BMHM Battery provides 300 flashes at 200ws with a Four Year pro-rate warranty. It uses a double deck of NiMh battery cells and is about 2.2 inches tall and weighs less than three pounds.