The Cospas-Sarsat System provides alerting services for the following types of beacons:
Beacons operating at 406 MHz and 121.5 MHz are compatible with the Cospas-Sarsat System; however, the operational capabilities of the System are different for these two types of beacons.
Sarsat satellites (but not Cospas or GEOSAR satellites) are also capable of relaying 243 MHz beacon transmissions. 243 MHz beacons have similar characteristics to 121.5 MHz beacons.
The Cospas-Sarsat Secretariat maintains a list of Cospas-Sarsat type approved 406 MHz beacons, manufacturers of type approved beacons, and beacon test laboratories recognised by Cospas-Sarsat.