This cable is used to connect the DJI Osmo Action 4 to the USB Type A plug. Back up of videos and photos from DJI Osmo Action 4 to an external memory stick in a convenient way. This USB Host adapter cable turns your DJI Osmo Action 4 into a USB host, allowing you to connect a USB Memory stick, a USB Drive or other USB Device to your DJI Osmo Action 4.