A standard Best Apex exit device can be retrofit to the Electric Latch Retraction option by ordering the Apex Electrification Kit. The ELR option provides remote Latch Retraction of exit devices. Continuous duty solenoids retract the latchbolt(s) for momentary unlatching or continuously for dogging. The ELR feature can be interfaced with automatic door operators, card readers, push buttons, toggle/key switches, and fire alarm systems. An ELR Conversion Kit REQUIRES an ELR150 Series Power Supply. Power may be supplied through a 4-wire continuous circuit hinge (furnished by others).