This tag is for questions relating to Uninterruptible Power Supplies designed to provide power when a normal supply fails; inside the scope are: custom units specifically designed for the Raspberry Pi; general units more often associated with PC hardware; and "home-brew" devices. (Usually) based on some sort of Battery technology and almost universally designed to replenish them when the normal supply that it stands in for returns.
For the main RPi units there are at least the following custom items:
