AceAbove 2600mAh Slim Air External Protective HTC One (M7) Battery Case - Black - Fits All Versions of HTC One 12 Month Warranty The powerful 2600mAh built-in battery can effectively double the battery life of HTC One (M7) Featuring a fully protective hardshell case with the minimum added bulk. Enjoy the comprehensive protection while still maintain the slim form factor of your HTC One. The case featuring a Micro 5 Pin USB cable input port Deploys the most reliable battery technology, which can live up to its standard and being rechargeable for more than 500 cycles The case also has the following functions built-in: charging switch, LED battery level indicator, charge & sync through the case, headphone jack cutout, function button cutouts.