The PERI Duo is the FIRST case for the iPhone® 5/5s and iPhone 6/6 Plus that integrates a hi-def, high-power Wi-Fi and Bluetooth enabled speaker system and a 2500mAh battery in a slim form factor. In addition to its speaker and battery functions, the Duo has an integrated hi-res DAC (digital-to-analog converter) and fully programmable single-chip audio DSP, offering true EQ (equalization) settings through the embedded DSP firmware. The Duo can also be configured to multicast music with multiple PERI Duo cases (up to 64!) through peer-to-peer Wi-Fi connectivity, creating an immersive audio experience loud enough to fill any room.