The full mortise, bearing hinge is recommended for low frequency doors. Use for common flush door/frame/wall applications. McKinney Concealed Circuit (CC) electric hinges allow a constant flow of current from the power source through the hinge to electrified door hardware. No external wires can be seen, eliminating disruption of power due to tampering or disconnection, and improving the aesthetics of the opening. Allows operation of devices requiring power such as electric locks, electric strikes, and electric latch retraction exit devices. 28 gauge wire standard. Four amp continuous @ 24 volts AC or DC per circuit 16.0 Amps intermittent duty (pulse) for 300 milliseconds. Hinges are supplied with 8" (305) leads as standard.