The x-ray machine is a medical tool that allows doctors to see inside the human body without having to make a single incision.

In 1895, physicist Wilhelm Conrad Rontgen discovered the x-ray , and modern science was never the same. The x-ray machine works by sending high-energy rays, similar to light rays but about 1,000 times shorter, into a patient’s body. These rays pass through the body, and then bounce off an x-ray detector located on the other side of the patient. According to the National Institutes of Health, the black and white x-ray image we see in the end is actually a “shadow” of high density objects that the rays were not able to pass through in the body.

Although a medical marvel, the x-ray machine does not come without it’s own set of risks. For example, the rays emit low doses of radiation. Prolonged exposure could cause harm to both patients and the x-ray technician. Due to this, patients are given heavy lead blankets to wear during exams that prevent the rays from hitting any part of the body other than the designated location.

Although commonly doctors use x-rays to diagnose broken bones, every now and then they see an x-ray image they’ll never forget. Because of the x-ray’s inability to pass through high-density objects, the tool allows doctors see strange objects that patients inadvertently get stuck inside them. Click on the video above to see a list of some of the strangest objects to ever have ended up on an x-ray image.