High quality chip, guarantee quality without false alarm Large detection range, 0~8 meters large detection range High-fidelity speakers, built-in 38 music, low consumption 150 meters distance, wireless reception, host position removable Multiple uses to meet different needs Can be used in hotels, hotels, shops, offices, homes, etc. Receiver operating voltage: 110-240V Transmitter operating voltage: 4.5V (3 batteries, 7 batteries) Receiver button: 1) Music: 38 music options, side music logo buttons to adjust 2) Volume: three-speed volume adjustment (high, medium, low) side volume indicator button to adjust 3) Can be set with sound and no sound (with sound: sound + indicator silent: indicator light) Working distance: up to 70 meters Transmitter sensing distance: 3-7 meters Receiver size: 76*80*33mm Transmitter size: 80*59*45mm Specifications: Product operation instructions: 1. Plug the receiver into the socket and turn on the detector battery cover to insert the battery. 2, the rotating bracket is stuck in the back of the detector 3. The detector switch is pushed to the ON position and waits for the self-test time of 10 seconds to enter the normal working state. Package Included: 1* receiver 1* transmitter 1* instruction manual   Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement.