Has anyone tried these? Or anything similar? These are for 2nd factor authentication with a separate piece of hardware, rather than an application on your device.
I might get one to use with my L5.

they are based in Italy from what i can tell …

Purism’s Librem-Key is similar but can’t use u2f YET right ?

I was goggling it for some time, but in the end decided to go with nitrokey (decided, not purchased it). their nano is very compeling (to me) but after some reviews (part of which I dismissed as unfounded) I had my doubts.
But for L5 you’d probably rather need pgp card

they say the firmware/software is open-source but i didn’t look deeper to see what kind of license is it covered by … if it’s APACHE like etcher-pro then i’m not interested …

It is, and reviews were around that code (and hardware design)

yes it’s APACHE 2.0 or MIT …

I picked a USB-C one two years ago for my android ( :scream:) but the android would not recognize it so I had to buy a yubi-key ( :sob:). I may pick up another one to try it again.

Something similar, yes. The Librem Key works the same way but with a USB-A connector. It doesn’t support FIDO2 but can use TOTP/HOTP for 2FA. Now that the Nitrokey software recognizes the Librem Key (and a recent bugfix in GPG makes it possible to put 521 bit ECC keys on the Key), it’s pretty painless to use.