Product parameters: 1. Receiver operating voltage: 110-240 V. 2. Transmitter operating voltage: 4.5 V (3 AA batteries) 3. Receiver buttons: 1) Music: 38 pieces of music are available, and the music logo buttons on the side can be adjusted. 2) Volume: three-level volume adjustment (high, medium, low), adjust the volume mark button on the side. 3) Sound and silence can be adjusted (sound: sound + indicator light, mute: indicator light) 4. Working distance: up to 70 meters 5. Transmitter detection distance: 3-7 meters. 6. Receiver size: 76*80*33mm 7. Transmitter size: 80*59*45mm 8. Package size: 17.5 x 11 x 7.5 cm. 9. Product gross weight: 0.22 kg net weight: 0.14 kg Packing list: 1X receiver 1X launcher 1 XInstruction manual Product operating instructions 1. Plug the receiver into the socket and turn it on, open the battery cover of the detector and insert the battery. 2. Place the rotating bracket on the back of the detector and lock it. 3. Push the detector switch to the ON position and wait 10 seconds for the self-test to enter the normal working state. Precautions: 1. Try to avoid installing the sensor in a place directly facing a strong airflow or near a heat source. (For example: cold air outlet, exhaust fan, electric stove or near the heater, etc.). Do not install the sensor directly in a place exposed to sunlight or rain, or near metal objects. 2, The sensor should be installed at a height of about 2 meters; the side detection of the sensor is more sensitive than a straight line (the human body directly faces the sensor). It should generally be installed on the side or top of the entrance gate, and). the sensor should be adjusted to a suitable position through the installation bracket to achieve an induction effect 3. The distance between the sensor and the receiver should be reduced as much as possible by obstacles and other wireless signal interference. Generally, the distance between the sensor and the receiver should be controlled about 20 meters under the obstruction of a wall. 4. If the doorbell has a short receiving distance or malfunction, please check the battery of the detector or replace it. 5. If the ambient temperature is too high (over 30 degrees), the detection distance of the detector will be shortened, which is normal. The product does not include batteries Note: The data are all measured manually, please allow 1-3cm error due to differences in light and display, there may be some color differences, please refer to the actual item received.