The Snake is designed to be a string of small batteries that can be fed into a confined space for example a lamp post. The battery can then power e.g. a camera. However in this arrangement the camera runs off either the mains or the battery pack. The camera is powered via the mains, however, when the mains power is unavailable to power the camera, the battery pack automatically takes over without a break in power. When the mains power is available it powers the camera whilst recharging the batteries.
A typical system as shown could be 4 x 6Ah giving 24Ah at 12 volts . Different Ah sizes are available if required.