ACR bought PLB1 and now they sell it, $250 - $300 selling price. It is smaller than the RescueMe smallest model. No fees, free international registration with NOAA, and they want you to update your information every 2 years. Worldwide coverage, sea and land. They don’t float. 7 year rating on battery. REI carries them.
The new 2 way satellite communication devices require a monthly fee but you can communicate with text messages and could allow for less than life threatening use, but some systems are not worldwide coverage. Garmin is a leader in these and has a very small one out now for about 2 years, worldwide coverage.
I also looked at Satellite phones which are the most expensive and bulky, better for boats or land use, and also are rentable for trips. Marine radios, bulky but getting smaller, limited range, $50 - $500 to buy, good lifeguard and coast guard contact since they monitor frequencies and give fastest response and some have gps location. Apple Watch with waterproof case, $10 add on monthly fee to phone, but can make cellular calls without phone if in range, one guy rescued off California with his while kiting. In U.S. by law, a cell phone can be used for 911 emergency calling without monthly plan so a small phone could be carried and used if charged.
PLB1 link: http://oceansignal.com/products/plb1/
Garmin link: https://buy.garmin.com/en-US/US/p/592606#overview
Article link on why kitesurfers need a PLB: https://www.thekiteboarder.com/2016/09 ... -need-one/
NOAA link: https://www.sarsat.noaa.gov/beacon.html