Don't know that brand, although there is a registry of EPIRB beacons you might be able to find it in (if it's not a rebranded one). So I'll just go over the general gist of it.
Before considering using it, validate that it's a 406 Mhz EPIRB and preferably one with GPS built in (else it will take 2 satellite passes by the LEO constellation before it's considered a valid alert, which can take up to 3 hours, versus 1 hour for GEO GPS plus a single LEO or MEO track) and if the battery life has not been exceeded, if there isn't an indication, then assume it is (battery life even if never activated is at most 5 years with the batteries typically used).
Then you'll need to register it at the local authority responsible for it (in the USA the NOAA for some odd reason, in most other countries the same authority that handles the issueing of IMSI's) and when doing it make sure that the country code for the beacon is set to your local one, else it will also need to be reprogrammed for that.
You will also need to figure out what it's activation mode is for ideal mounting.
But honestly I would suspect it's an old 121.5Mhz EPIRB or at least an older 406Mhz one, if it's a 121.5Mhz EPIRB, unless you happen to be near regular airline routes, they are worse then useless. The older 406Mhz ones can be used on condition of what I mentioned above.
For reference new beacons start at $400 with GPS support although sometimes you can find deals on them for around $250. I'd also consider a SART-AIS (show up on radar and chartplotter of ships) and waterproof marine VHF (with replacable batteries and spare ones) if you'd go the full outfitting option.
The BEEPA EPIRB was made by Sea Land and Air Communications Ltd (Sea Air & Land Communications Ltd. - Designers and Manufacturers of Communications Systems.) out of New Zealand. It broadcases on 121 and 243 Mhz. It is old however it has some advantages over the new systems. First, it uses C cell batteries you can replace them yourself, even in a life raft. The new systms usually require you to send them back to the factory every five years. The new ones can't be replaced in a lifeboat. Second, a set of batteries broadcasts for seven days versus two days for most new EPIRBs.
As mentioned above, the 406Mhz systems have some advantages but also some disadvantages. I would keep it and have it ready for use. If you want to use a 406 Mhz system that is fine, but this is not an either-or situation. Each has advantages so make good use of the strengths of each.