(4) polk audio db652 6.5" 300 watt car audio marine/atv/motorcycle/boat speakers polk audio .500 mah battery supports 10 hours of playback! this battery lasts longer than almost any other on the market!. charge time: 1-2 hours. extremely loud and powerful in a handheld compact size. material: 100% rohs silicone & abs this enclosure design delivers top of the line sound quality. perfect for running, camping, hiking, pool, beach, shower, bedroom, ipad/laptop speaker, kitchen and many other applications. includes aluminum hook to latch it onto anything from your shirt, to a dog leash, a pocket book, etc. bluetooth version. 4.0 with edr (enhanced data rate). a2dp audio streaming 40 foot max bluetooth range. automatically remembers and syncs with previously synced devices. playback controls - play, pause, skip forward, skip back, volume up, volume down. will control next song, pause, play on popular apps like pandora, spotify, and others. can control next song, pause, and play from the bluetooth speaker. the built-in mic allows you to speak through the device so you can make and receive phone calls hands-free. circular design fits in the palm of your hand or in your pocket. rugged and shockproof!. rubberized impact-resistant rubber feet for great sound when placing speaker on any hard surface. compatible with any bluetooth devices such as ipad, iphone, laptops, android phone, other cell phones, ipods, other bluetooth mp3 players. distortion: less than 1 %. natural sound with enhanced bass response. frequency response: 150hz 18khz. built in advanced speaker design with horn speaker unit for increased output power. dimensions of unit (inches): 3.35 x 3.43 x 1.34 height. unit weight: 0.3 pounds. 90 day money back guarantee!