The regular (only usb a) is out of stock. They have a dual (a & c) which probably will be a better choice and have 323 available
interesting that they have 50 and 128 passkey models, but if you are going to use it for a while, probably 300 won't be enough.
TOKEN2 Sàrl is a Swiss cybersecurity company specialized in the area of multifactor authentication. We are a FIDO Alliance member.
FIDO2 USB Key, U2F USB Key, Cheap Yubico alternative, FIDO2, fido alliance certified security keys Replace your mobile authenticator with secure hardware OTP token! Easily programmed via NFC. Designed to use with Google, Facebook, Dropbox, GitHub, Wordpress, Office 365, Azure MFA etc.
www.token2.com
interesting that they have 50 and 128 passkey models, but if you are going to use it for a while, probably 300 won't be enough.
If you don't require 300 passkeys, you might want to consider a more cost-effective option like the T2F2-Dual model, with 50 passkey storage and regular PIN firmware or T2F2-PIN+/Dual model, with 50 passkey storage and PIN+ firmware.