The full mortise, plain bearing hinge with a non-removable pin is recommended for standard weight, medium frequency doors or doors with closing devices. Use for common flush door/frame/wall applications. Each hinge features concealed plug connectors that eliminate the need for separate or exposed wiring. Standard connectors make installation quick and simple. Brass eyelets add protection and durability. 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 tampering and improving the aesthetics of the door opening. For 4 amp continuous @ 24 volts AC or DC per circuit, 28 gauge multi-strand wires are used. An 8 position connector is used for QC4 and QC8 wire hinges. An 8 position and a 4 position connector is used for QC12 wire hinges. Electric hinges should be installed in the center position on the door. Installation instructions are packed with each hinge.