Tiny satellite design. 2. 5″ full range driver for satellites. 4″ bass driver for subwoofer. Plug & play USB/SD card reader. USB reader supporting MP3/WMA dual formats decoding. Play/Pause, Next, Previous three buttons for USB/SD reader control. Center rotary volume knob on front panel. Bass control on back panel. Blue LED as power indicator. Wooden cabinet delivers strong and low distortion bass.