Door Station, Indoor/Outdoor, Surface Mount, Height (In.) 6 51/64 in, Width (In.) 3 7/8 in, Depth (In.) 1 in, Door Station Height (In.) 1 in, Door Station Width (In.) 10 in, Door Station Depth (In.) 1 in, Master Depth (In.) 1 in, Master Height (In.) 6 51/64 in, Master Width (In.) 3 7/8 in, Talk Channel Output (W) 50 Watts Peak (25 Per Channel), Listen Channel Output (W) 50 Watts Peak (25 Per Channel), Wiring Conductors 2 Conductors, Wire Type Non-Shielded, Power Source 24V DC, Voltage 24V DC