With anti-theft function. When this is shaken, 6 beeps in turn, which adds a car search and overtaking the alarm function. Support SD cards for playing mp3 music and fm. Support the power of memory to play, and it plays previous music when you turn it on. wireless remote control. Technical specifications: Operating voltage: 12 V Audio channel: 2 sound channels (stereophonic) fm radio frequency: 87.5-108.0 MHz Supported SD memory cards: 128 MB-4 GB Alarm sound: 125dB wireless remote control: about 10 m.