There are several types of YubiKey options for you to choose from depending on your needs and budget.  Below is summary information for each type and a link to purchase from Amazon.  Carefully consider what type of computer port you will be inserting the device into, because a YubiKey must be inserted in the USB port of the computer you are using in order to authenticate.  You'll need to make sure that your USB port is easily accessible (e.g. on a laptop computer). To help you determine which YubiKey style will work best for your computer and needs, take this short quiz from Yubico., as well as reviewing this comparison chart.

Each time you need to login with two-step authentication, if you select Security Key you will then need to touch the YubiKey that is inserted in the USB port of your computer.

Connects to USB-A computer port:

• YubiKey 5 NFC - Fits USB-A computer ports and designed to stay in port. Touch-based authentication for NFC-supported Android devices and applications. (Not currently supported for iOS devices).
• YubiKey 5 Nano - Fits USB-A computer ports and designed to stay in port for convenience. 

Connects to USB-C computer port:

• YubiKey 5C Nano - Fits USB-C computer ports and designed to stay in port. 
• YubiKey 5C - Fits USB-C computer ports and designed to fit on your keychain.

 If you have a YubiKey, you can follow the instructions for enrolling it.

Note: Not all browsers or applications support use of a YubiKey, including the current version of the Cisco Secure Client VPN on MacOS.  Please review the information on your selected YubiKey to determine compatibility.