Access Control Phone System, Color Silver, Stainless Steel, Number of Lines 1, Ringer Yes, Mounting Type Flush, Surface, Height 11 3/4 in, Width 9 3/4 in, Depth 3 1/2 in, Volume Control No, Power 16V AC, Voltage 16V AC, Output Rating 10A AC/7A DC @30V, Operating Temp. Range -22 Degrees to 149 Degrees F, Requires Telephone Line, Includes Mounting Hardware