A 510(k) submission is a premarket notification required by the U.S. FDA for most Class II and some Class I medical devices before they can be marketed. It demonstrates that the new device is substantially equivalent to an already legally marketed device, known as a predicate. The submission includes detailed information such as device description, performance testing, labeling, and safety data. FDA reviewers evaluate the documentation to ensure the device poses no new risks compared to the predicate. Overall, a successful 510(k) submission allows manufacturers to legally market their medical devices in the United States.