Karnotech REMAX Bluetooth Speaker Portable Desktop Multi-Function Power Bank Bluetooth 4.0 Wireless Outdoor PC Car Subwoofer Speakers, RB-HI Silver * 8 main functions: NFC function, hands-free call, Shoulder strap, Bluetooth 4.1, Micro SD,, MENTALCASE, 2.1 CHANNEL, AUX cable. * Aluminum alloy full mental textured shell and fine carving sound holes pose a great image of qualified speaker. * High-performance Bluetooth 4.1 version NFC connection, enable stable signal and efficient connection; Short-distance NFC, low-energy consumption, fast and safe connection. * SD card reader function: support of reading and playing files stored in SD card. * 3.5 mm Gold-plating audio line: 3.5 mm international-standard socket, excellent connecting and stable transmission of timbre.