JTD Portable Wireless Bluetooth Speaker W/ 3D Surround Stereo Sound & Full Metal Housing - Wireless,& Hands-Free & 8hrs Playtime & 30ft Bluetooth Range (3D-Surround Gold) DSP ENHANCED SURROUND CHIP - Advanced 3D surround and subwoofer stereo audio performance delivers a full-range listening experience FULL METAL CASE - Most compact and best Bluetooth speaker with a full metal housing and intelligent body with, creative design LATEST BLUETOOTH - Latest CSR Bluetooth 4.0 technology can be easily and quickly paired with all bluetooth-enabled devices HIGH CAPACITY BATTERY - Built-in high capacity rechargable battery plays wirelessly whenever you play up to 8hours & HANDS-FREE CALLS - Built-in microphone for picking up calls Updated the Bass sound performance, especially for the Bluetooth connectivity stability.