The NOR Gate is one of numerous blocks added by the RedPower 2 mod that allows for Redstone circuitry simplification. The NOR Gate is a gate which outputs power if it is not receiving any power from any of its input faces. If any of its three input faces are receiving power, then its output power will be turned off. As with other RedPower blocks that simplify wiring, a Screwdriver can be used to switch whether or not one of the inputs is disabled.
