Feature: 1. WIRELESS OPERATION: The wireless service calling system uses RF wireless technology, offering convenient operation and compatibility with various environments. 2. WATERPROOF DESIGN: The watch receiver features IPX7 waterproof rating, while the transmitter has an IPX4 rating, ensuring durability and reliable performance. Operating frequency is 433.92MHz with high sensitivity. 3. SUPPORT MULTIPLE CHANNELS: The wireless paging system includes 4 channels and supports up to 4 transmitters, allowing flexible configuration and versatile application. 4. LONG ENDURANCE: Built-in high-capacity battery provides extended standby time. Rechargeable design with low power consumption for continuous use. 5. APPLICABLE LOCATIONS: Suitable for home, factory, hospital, and other settings, ideal for elderly care and emergency alert situations. Specification: Item Type: Wireless Restaurant Service Calling System Material: ABS Watch Receiver Parameters: Operating Frequency: 433.92MHz Charging Voltage: DC5V Battery Type: 300mAh Lithium Battery (included) Operating Current: 100–20mA (Vibration and Buzzer Mode), 75–10mA (Vibration Mode) Standby Current: 10–5mA Receiving Sensitivity: -107±2dBm Decoding: Learning Code Waterproof Rating: IPX7 Operating Temperature: -20°C to 60°C Pushbutton Transmitter Parameters: Operating Frequency: 433.92MHz Size: Approx. 60x60x13mm / 2.4x2.4x0.5in Battery Type: 2 x 240mAh CR2032 Batteries (included) Transmit Current: 10–3mA Standby Current: <1uA Open Distance: >100 Meters Keystroke Life: 1 Million Times Waterproof Rating: IPX4 Operating Temperature: -20°C to 55°C Function: CALL Package List: 1 x Receiver 4 x Transmitter 1 x Charging Cable 1 x Instruction Manual Note: All data are measured manually; slight variations may occur.