A water and/or airtight electrical socket for portable electronic devices includes sealing elements that are shaped like an arc, and arranged to seal only a portion of the perimeter of the socket-plug interface. When this arc element experiences pressure, it will mechanically relay the force caused by the pressure only to that section of the perimeter of the socket-plug interface that it is arranged to seal. It will not relay mechanical forces any further. This way, the mechanical effect of any extra asymmetric pressure will simply be limited to increasing the pressure of the seal in the perimeter section of that particular sealing element, thereby tightening the seal further still. This allows the socket opening to be sealed in a water- and/or airtight manner even in asymmetric pressure conditions, both when there is no plug in the socket and also when a plug is inside the socket.