Telephone Entry System Color Silver Stainless Steel Number of Lines 1 Ringer Yes Mounting Type Surface Height 6 1/8 in Width 10 in Depth 5 1/4 in Volume Control Yes Power 16 V AC 20 VA Voltage 16 V AC Output Rating 20 VA @ 16 V AC Operating Temp Range 10 Degrees to 145 Degrees F Requires Internet Connection Includes 16 VAC 20 VA Power Transformer