Catalog > Consumer Electronics > Security & Alarms > Access Control > Video Doorphones Commax 4 Button Entry Station 4 Button Entry Station CMX DR-4UM Commax DR-4UM 4 Button Entry Station Call for Price Add Specifications, Prices & Availability may change without notice. Images are for illustration purposes only. E&OE Features 4 button wide name plateMaterial : AluminumHouse call and talk Specifications Power Source : DC 12VData Transmission : 3 Wire in Common +1 WireCommunication : Hands-Free TypeDisplay Device : LED lightDimension(mm) : 130(W)×315(H)×10(D)Installation Hole Size : 110(W)×284(H)(mm)Fillupbox Size(mm) : 122(W)×305(H)×37(D)