NewEastRock Bluetooth 4.1 Wireless Speaker, natural sound, portable, hand free call, work for iPhone iPad Android or Desktop Devices with MP3 Player and Microphone (green) Powerful amplifier delivers natural sound. Built-in rechargeable lithium polymer battery supports up to 7 hours of playtime. The speaker looks like a trunk, and a tiny body allows you to carry it wherever you go. Wireless speaker comes with Bluetooth 4.1 that is compatible with most Bluetooth-enabled devices within 30 feet. Built-in microphone/voice prompts for hands free call. Connect non-Bluetooth media devices via 3.5 mm Aux cable.