In some implementations, the mounting plate 800 includes a first fastener structure 806 located at a first end of the mounting plate 800, and the first fastener structure 806 is configured to mate with a second fastener structure 726 located at a corresponding end of the rear exterior surface of the device housing 702. The device housing 702 is mechanically fixed onto the mounting plate 800, when the first and second fastener structures are fastened to each other. In some implementations, the mounting plate 800 includes a third fastener structure 808 located at a second end of the mounting plate 800, and the third fastener structure 808 is configured to mate with a fourth fastener structure 728 located at a corresponding end of the rear exterior surface of the device housing 702. The device housing 702 is mechanically fixed onto the mounting plate 800, when the first and third fastener structures 806 and 808 are fastened to the second and fourth fastener structures 726 and 728, respectively. In a specific example, the third fastener structure 808 includes an extended holding structure, and the fourth fastener structure 728 of the device housing 702 includes a recess hole configured to receive the extended holding structure. The extended holding structure may be pulled out of the recess hole of the device housing 702 when the device housing 702 slides along a longitudinal direction 812A or a transversal direction 812B, but not when the device housing 702 is pulled by a separation force having a direction perpendicular to a front exterior surface of the device housing 702.