1. Adopts passive infrared detection technology. 2. Detection distance of the PIR motion sensor is up to 5 meters. 3. Detection angle of the PIR motion sensor is 120 degrees fan-wise. 4. Built-in high quality MP3 player with 8MB flash memory. 5. Equipped with a MP3 player plate and easy to operate. to copy audio files from the USB stick into the internal flash memory. to play back audio files directly from an inserted USB stick or micro-SD card. Supports max. 32GB USB stick and max. 32GB micro-SD card. Built- D 10Watts amplifier and the sound quality is beautiful. Supports three work modes: same track playback mode, next track playback mode, and random playback mode. An AC to DC power adapter comes with the device. Two clamps attached with the player and easy to install on the ceiling. Working Voltage: 12V-24V DC Working Current: ≥1000mA Standby Current: ≤10mA Audio Format: MP3 Audio Output Power: ≤10Watts Detection Range: ≤5m (120 ° angle) Color: As Shown Material: Plastic+Metal Package Contents: 1 x Ceiling Speaker Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.