xfire on Nostr: what is a physical keeper? like not on a computer? I have two hw wallets. one is ...

what is a physical keeper? like not on a computer?

I have two hw wallets. one is close to me, the other is as far away as I could manage. the pin is not documented, just memorized. passphrase are memorized & documented at different locations with friends/family. there exists a bank vault with my seed words on paper.