Buzzer alarm: Volume up to 130dB, alert to 10 minutes; built-in backup battery, can operate for 12 hours even during power outages. Simple device provides multiple layers of protection: When disabled or elderly people encounter emergencies and need help, pressing the emergency button immediately trigger an alarm. No wiring is required, and installation is simple. Audible and visual alarm, no wiring required: In an emergency, pressing the call button activates the receiver, which activates an audible and visual alarm upon receiving the wireless signal. The sound can reach 120 decibels, and the alarm light flashes simultaneously, providing a strong warning. Name: Wireless Sound and Light Main Unit Configurable Capacity: 20 Sub-units Power Input: DC 9-15V 500mA Alarm Method: Alarm sound, flashing light Receiving Frequency: 433MHz Receiving Distance: Approximately 300 meters in open areas Alarm Loudness: 0/80/100/130db selectable Sound Duration: 0.3/1/3/10 minutes selectable Alarm Current: Less than 150mA Built-in Battery: AAA 6V, usable even after power failure Product Accessories: SOS button, remote control, power supply, instruction manual Product Dimensions: 200 x 112 x 62 mm Plug Type:EU Plug,it applies to Indonesia, Germany, France, Spain, Italy and so on. Voltage: AC220V Color: White Material: plastic Package Contents: 1 * Audible and visual alarm 1 * SOS button 1 * Power supply 1 * Remote control 1 * Chinese and English instruction manual Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.