A rotary switch fitted with signalling means to provide a visual indication of the operating condition of an actuator device, comprising a switch body made of metal or coated externally in metal and a cover is provided. The cover may be joined to close the switch body by means of a plurality of attachment screws in metal or externally coated in metal, each housed in seats arranged in the cover and in the switch body. In particular, inside the seat of the switch body there may be an insert made of a material suitable to prevent the circulation of galvanic currents between the seat of the switch body and the attachment screw.

Implantable medical systems include implantable medical leads that have magnetic orientation-independent magnetically actuated switches that are placed in the conduction path to the electrode of the lead. Thus, regardless of the orientation of a substantial magnetic field like that from an MRI machine to the lead and switch within the lead, the switch opens when in the presence of that substantial magnetic field. The switch may be placed in close proximity to the electrode such that the opening of the switch disconnects the electrode from the majority of the conduction path which thereby produces a high impedance for RF current and reduces the amount of heating that may occur at the electrode when in the presence of substantial levels of RF electromagnetic energy as may occur within an MRI machine.

A method of manufacturing a translucent keycap is firstly to form a translucent base layer to overlay a top surface and a skirt side surface of a translucent main body. Next, a light-shielding layer is formed to overlay the translucent base layer. Subsequently, a removable intermediate layer is formed to at least overlay the light-shielding layer located on the top surface. Afterward, on the removable intermediate layer over the top surface, a hollowed region is formed through the removable intermediate layer and the light-shielding layer such that the translucent base layer is exposed within the hollowed region. Then, a colored translucent layer is partially formed to cover the hollowed region and the removable intermediate layer located on a peripheral of the hollowed region. Finally, the removable intermediate layer and the colored translucent layer covering the removable intermediate layer located on the peripheral of the hollowed region are removed together.