SallyBest&reg; Digital Car Power Amplifier MMC MP3 SD USB Audio Player Reader 3-Electronic Keypad Control with Remote Control Compatible with format MP3 in memory type USB or SD. Support USB / SD / MMC memory card input. 3-Electronic keypad control. Power on/off control and remote control. 100% Brand new, high quality, easy and convenient to use. Revolutionary amplifier technology, ultra compact design, light weight.