Features: Quick Calling: When there is emergency, just push the call button, and the alert message will immediately send to the receiver. Stable Signal: The working range can get up to 1000 meters in open area, making sure that you will never loss a call in night. Alerting Mode: Has 3 kinds of alarming modes, flashing and vibration, flashing and buzzer, flashing and vibration and buzzer. Extensive Use: Can be widely applied in home, nursing home, hospital and so on, suits perfectly for the elderly, patient, Easy Carrying: Comes with a light weight and a compact size as well, suitable for both indoor and outdoor, safeguarding the safety. Specifications: Component:ABS Operating Frequency 433.92MHz Charging Voltage: DC5V Working Voltage: DC3.7V Lithium Battery Model: 602030 Battery Capacity: 300mAh, included. Working Current: 100±20mA in vibration and buzzer mode, 75±10mA in vibration mode. Standby Current: 10±5mA Receive Sensitivity: -107±2dBm Decoding: Learning Coding Waterproof Grade: IPX7 Working Temperature: -20℃~ 60℃ Operating Frequency 433.92MHz Material: ABS Battery Type: 1 x 23A12V battery. Battery Capacity: 80mAh, included. Emission Current: 10mA±3mA Standby Current: <1uA Open Distance: Approx. >1000m / 3280.84ft Keystrokes: 1000,000 times Waterproof Grade: IPX4 Working Temperature: -20℃ ~ 55℃ Single Key: Call Size:Approx.9cm/3.54inch Package Includes: 1Pc Receiver 1Pc Button note: 1.Please allow 1-2cm errors due to manual measurement, making sure that you not mind before order. 2.Due to the differences between different monitors, the picture may not reflect the actual of the item.