Monoprice CaseDuo HD Media Dock for HTC Droid DNA - Retail Packaging - Black The dock has a plastic insert which when installed provides a perfect fit if no case is present and when removed provides a perfect fit with most types of cases installed on the phone While the dock can charge your phone the primary value is the built-in MHL adapter which converts the 1080p video from the phone's micro USB port into an HDMI signal for direct output to any HDMI capable display or repeater The dock supports all High Speed HDMI features including 7.1-channel audio and 3D video