My device for the Mars Medical Challenge is the mirror-brush. The mirror-brush is a combination of a toothbrush and a dental mirror. It is a dental tool, so it is considered a medical item. It is useful because you use the mirror to look inside your mouth to see where your teeth need to be cleaned, or where a cavity is, then you can use the toothbrush to clean your teeth. A toothbrush/dental based item is useful especially on the trip to Mars because the average human goes through roughly 6 toothbrushes a year, so it will become a must to be able to 3D print the toothbrushes during the trip, since it is about 3 years long. Using math, that is a total of 18 toothbrushes per astronaut, just for the ride there! The mirror-brush will be lightweight, and easy to carry around and deal with. It will be made out of plastic on the handle, metal on the mirror, and small nylon bristles on the brush. In conclusion, my tool, the mirror-brush, will be a much needed item to be 3D printed on the trip.