Features: Double alerts System with 120dB electric bells and rotating beacons ensures visual and auditory alarms in noise environment (90dB+), with IP54 rate ABS housing for dust/water resistance. plugs and play installation connection directly to telephone lines and 220V power, automatically detecting rings signals and halting alerts during calls for smooth communication accessories integration. Industrial workers and facility managers in factories, mine, or warehouse will appreciate this industrial alarm system that overcomes ambient noise interferences. designs for harsh conditions like steel mill and dusty quarries, it activates alerts through incomings calls while supporting remote start security warnings against intruders. This telephone rings boosters maintains standard phone functionality while adding emergency notification capabilities, requiring no wiring modifications for rapid deployment in critical environment. Specifications: Material: ABS Product size: Length 85×Width 65×High 22mm/3.4x2.6x1inch Package Includes: 1xTelephone rings boosters note: 1.Please allow 1-2cm errors due to manual measurement, make sure that you do not mind before you order. 2.Due to the differences between different monitors, the picture may not reflect the actual colorful of the item.