Yubico YubiKey 5 Nano - Two Factor Authentication USB Security Key, Fits USB-A Ports - Protect Your Online Accounts with More Than a Password, FIDO Certified USB Password Key, Extra Compact Size
The YubiKey 5 Nano combines hardware-based authentication and public key cryptography to protect against account takeovers. Simply insert into a USB slot and authenticate with a touch. YubiKey 5 authentication is four times faster than typing a One Time Passcode and does not require a battery nor network connectivity so it is always accessible.

Yubico YubiKey 5C - Two Factor Authentication USB Security Key, Fits USB-C Ports - Protect Your Online Accounts with More Than a Password, FIDO Certified USB Password Key
The YubiKey 5C combines hardware-based authentication and public key cryptography to eliminate account takeovers. Simply insert into a USB-C slot and authenticate with a touch. YubiKey 5 authentication is four times faster than typing a One Time Passcode and does not require a battery nor network connectivity so it is always on and accessible.