A housing mechanism (100) includes a main body (60) and a shield/cap (70). The main body accommodates an inner interface and defines a port (63) therein. The port is configured for allowing an outer interface to be inserted into the main body and for thereby engaging the outer interface with the inner interface. The shield is located near the port and is selectably rotatably positionable between a first position, in which the shield covers the port, and a second position, in which the shield does not cover the port. The first position and the second position cooperate to form an angle therebetween.