Audible Alarm Type Bell, Visual Indicator Type No Visual Indicator, Voltage 24V AC, Decibels 88 dB, Sound Pattern Continuous, Indoor/Outdoor Indoor, Outdoor, Mounting Surface, Height 4 in, Width 4.5 in, Depth 2.4063 in, Diameter 4.5 in, Vibrating Yes, Housing Material Steel, Features Weatherproof By Adding Appropriate Back Box, Standards FM, UL Listed, Amps 0.250A, Color Gray, Includes Hardware, Bell