PLBs, approved for use in this country last July, are smaller, easier to carry and less expensive than EPIRBs, but they also have slightly lower performance characteristics.
They have less battery power; an EPIRB can transmit for 48 hours, a PLB for 24 hours. An EPIRB will float upright and transmit its distress alert. A PLB isn’t required to float, although some do but not necessarily upright. An EPIRB is waterproof to 10 meters, a PLB to 1 meter. An EPIRB has a strobe light; a PLB does not. And a PLB must be manually activated. Both types of beacons transmit a digital signal with the name of the owner and boat, key contacts, and phone numbers embedded in it.
Street prices for a 406 EPIRB range from about $800 to $1,400 depending on features. A 406 PLB can be purchased for less than $600.