A layer-structured, open-design keyboard includes a main body and a tray attached to the main body from below. The main body has key mechanisms and keycaps mounted on tops of the key mechanisms. The main body includes an upper-layer plate, a middle-layer plate, a circuit board, and a lower-layer plate arranged from a top to a bottom of the main body successively in a spaced manner, so as to define three clearance spaces that communicate the interior of the main body with the exterior.

An electrical device such as, for example, a battery-powered electrical switch is disclosed. The battery-powered wireless switch includes one or more mechanisms arranged and configured to provide simplified access for servicing (e.g., replacing) the batteries located within the wireless switch. In one embodiment, the wireless switch is arranged and configured so that the batteries may be accessed by reconfiguring the wireless switch from a first closed position to a second opened position to access the batteries. Thus arranged, removal of the wireless switch from a wall-box or a surface of a wall is not required, the user may only need to remove the wall-plate in order to reconfigure the wireless switch. In one embodiment, at least a portion of the wireless switch is pivoted from the first position to the second position to provide access to the batteries.