This is a new OEM Charging Connector Flex with Mic for Samsung S2 GT-I9100, it's stuck with glue to the front panel.If your phone has problems in charging and transferring data,then you need this new repair part.
http://www.hytparts.com/000338-oem-new-usb-charging-port-dock-connector-with-mic-repair-part-for-samsung-galaxy-s2-i9100.html