Product Description Overview:The Command Access ETH4W5K4040 625 CH-BB79 Energy Transfer Hinge is a 4-wire, 5-knuckle, standard weight hinge designed to discreetly transfer 26-gauge low-voltage power from the door frame to locking hardware. With its concealed wiring, it provides both a tamper-resistant and professional finish for commercial door installations. Specifications: SKU: ETH4W5K4040 625 CH-BB79 Size: 4″ x 4″ Finish: Bright Chromium (625) Weight: Standard weight hinge Design: 5-knuckle, full mortise Wire: 4-wire, 26-gauge conductors for low-voltage transfer Application: Interior or exterior commercial doors Hinge Type: Energy Transfer Hinge (ETH) Typical Uses: Electric mortise & cylindrical locks Electric strikes (especially for paired doors) Electrified exit trims & latch pullback devices Door-mounted card readers Low-voltage door lighting Features & Benefits: Concealed wiring for clean, tamper-resistant installation Provides dependable low-voltage power transfer without restricting door movement Compatible with a variety of electrified locks and access control devices Bright Chromium finish offers a sleek, high-end appearance Built for long-lasting performance in high-traffic commercial settings