I watched the battery drain a percent every couple of minutes when using my Hidizs portable as a transport into a hifimediy UDA38 pro dac which draws power from the USB device regardless of whether it is plugged in or not to a separate power supply (it has both options). This dual head cable resolves the issue. I have the power side plugged into an independent supply, and the data side plugged in through an adapter to the Hidizs AP80. No problems about handshaking, and now the transport works without draining the battery. I have not had it long but the sound is very clear and open, and most certainly an upgrade on a basic USB cable. Feels well made. Apparently silver plated / hand made etc though this is not in the audiophonics description (doukaudio). Feels much better made than appears in the photos. v happy.