JBL Control X Wireless Portable Stereo Bluetooth Speakers, Red Battery-powered stereo Bluetooth speakers without the wires 30W Class-D digital amplification High Definition Imaging (HDI) waveguide with 1 (25mm) CMMD Lite tweeter 5.25" (133mm) polypropylene graphite-filled cone woofer Rugged, contemporary design for indoors or on-the-go