The "S" Series Blocks are designed for power hungry cinematic camera rigs and applications requiring battery voltages of 14.4v or 28.8v nominal. The "S" Series provides maximum output power efficiency in three sizes, 400Whrs, 600Whrs or 800Whrs. The "S" Series has proven to be a workhorse on many 14.4V cameras as well as a powerful and reliable 28.8V power source for all Alexa cameras.