Feature: 1. WIRELESS TECHNOLOGY: The wireless calling system utilizes high performance wireless technology, ensuring a stable and reliable connection. It is suitable for various venues and can meet the demands of large scale usage, providing efficient communicate and excellent paging results. 2. LIGHTWEIGHT AND PORTABLE: The wireless calling system is small, lightweight, and easy to carry. Its simple design adds a touch of style, while its portability allows for convenient mobility, making it suitable for various environments. 3. TIME DISPLAY: With a built in time display, the receiver shows the time, date, and day, making it easy to record call times accurately. This feature enhances workflow efficiency and helps to convenient operations. 4. WIDE APPLICATION: The wireless calling system is suitable for a wide range of applications, including homes, hotels, bars, restaurants, factories, and more. It offers a reliable and efficient communicate solution in various settings. 5. RELIABLE AND STABLE: Built to withstand demanding environments, the wireless calling system features an IPX4 waterproof rating and high sensitivity receivers. It is designed for long lasting durability and reliable performance, ensuring it can withstand daily use and challenging conditions. Specification: Item Type: Wireless Calling System Model SU‑620 Receiver with Display: Operating Frequency: 433.92MHz Size: Approx. 210x140x30mm / 8.3x5.5x1.2in Material: ABS Receiving Sensitivity: 105dB Decoding: Learning Code Waterproof Rating: IPX4 Operating Temperature: ‑20℃ to 60℃ Button Transmitter: Operating Frequency: 433.92MHz Material: ABS Battery Type: Lithium Battery Battery Type: 2 x CR2032 Battery Battery Capacity: 240mAh (included) Transmit Current: 10±3mA Standby Current: 200 Meters Keystroke: 1 Million Times Waterproof Rating: IPX4 Operating Temperature: ‑20℃ to 60℃ Double Key: CALL, CANCEL . Package List: 20 x Button Transmitter20 x Adhesive Sheet1 x Instruction Manual1 x Display Receiver1 x Power Adapter Note: All data are measured manually, and there are certain errors in the measurement results.