Notes: The product is packed in a neutral color box, and the product specifications are two kinds of European and American regulations. Please note the specifications when purchasing Product Parameters:1. The operating voltage of the receiver: 110-240V2. Transmitter working voltage: 4.5V (3 x AAA batteries)3. Receiver button:1) Music: 38 pieces of music can be selected, and the music logo button on the side can be adjusted2) Volume: three levels of volume adjustment (high, middle, low) side volume sign button to adjust3) You can adjust sound and silence (sound: sound + silent indicator light: indicator light)4. Working distance: up to 70 meters5. Transmitter detection distance: 3-7 meters6. Receiver size: 76 * 80 * 33mm7. Transmitter size: 80 * 59 * 45mm8.Packing size: 17.5 * 11 * 7.5cm9. Product gross weight: 0.16kg net weight: 0.12kgpacking list:1 X receiver1 X transmitter1 X manual Product usage instructions 1. Plug the receiver into the outlet and turn it on, open the detector battery cover and insert the battery.2. Place the rotating bracket on the back of the detector and lock3. Push the switch of the detector to the ON position and wait 10 seconds for the self-test time to enter the normal working state. Precautions:1. Try to avoid installing the sensor in a location directly facing the large airflow and close to the heat source. (Such as: cold air outlet, exhaust fan orifice, electric stove or heater nearby, etc.). Do not install the sensor directly in a place exposed to sunlight and rain, or near metal objects.2,The sensor should be installed at a height of approximately 2 meters; horizontal detection of the sensor is more sensitive than linear detection (the human body is directly facing the sensor). Typically, it should be installed on the side or top of the front door and the sensor should be set in a suitable position via the mounting bracket. Get the best detection effect3. Interference between the sensor and the receiver should be minimized as much as possible. Under the obstruction of a wall, the distance between the sensor and the receiver should be checked at about 20 meters.4. If the doorbell has short receiving distance or malfunctions, please check the detector battery 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 a normal phenomenon.