Explanation: The "automatic release mechanism" in this context refers to a Hydrostatic Release Unit (HRU), commonly found on Emergency Position-Indicating Radio Beacons (EPIRBs). These vital safety devices are designed to automatically deploy an EPIRB if a vessel sinks to a certain depth. To ensure their reliable operation in an emergency, international maritime safety regulations, specifically the Safety of Life at Sea (SOLAS) convention, mandate that HRUs be replaced every two years from their date of manufacture. The Federal Communications Commission (FCC) enforces these regulations for maritime radio equipment used on U.S. vessels. This regular replacement prevents the mechanism from degrading over time, ensuring it functions correctly when needed. Intervals other than two years do not meet these crucial safety standards.