MK-VR
MICRODOT CAMERA

Under normal circumstances your MK-VR microdot camera should not require much maintenance or care. Clean hands, careful photographic habits, and proper storage will greatly reduce the need for cleaning.
The exterior finish is very chemical & dirt resistant. It is also exhibits reasonable abraision resistance, but coins and other metal objects can certainly damage the finish especially in the slots in the camera back. If this is a concern, you should avoid using coins to open the back. The back should never be installed so tightly that it cannot be removed with simple finger pressure. Refer to this video to see how to install and uninstall the camera back using your fingers.
Cleaning the exterior of the camera may be necessary from time to time. Generally a damp cloth with water, soapy water, window cleaner or other common all purpose cleaner will easily remove any dirt that may have accumulated over time. Warning, the operative word here is damp. Too much water can push dirt and moisture into the interior of the camera and clog or bind in areas such as that between the rotator and case or other parts.
The objective may also need occaisional cleaning. Care and cleanliness can reduce the frequency of cleaning the optics. There are several lenses that make up the optical system or objective. The only lens you should ever attempt to clean is the top lens. The top lens is the element you see when you open the shutter.