#enos is good because it's cheap, doesn't require licensing nor registration and since it's not using emergency radio bands, is not susceptible to costly false alerts...

Personally, I did consider buying my own #ENOS beacon as a #diver since it's cheaper than any other #EPIRB and can be really helpful in areas of strong currents where it's impractical to swim.
https://en.wikipedia.org/wiki/ENOS_Rescue-System
https://en.wikipedia.org/wiki/Emergency_position-indicating_radiobeacon