CIPTOR FIDO  U2F key
The FIDO (Fast Identity Online) Alliance is an industry consortium producing standards for authentication without passwords. Designed for both One-Time Password and Biometric authentication factors, FIDO READY™ devices allow users to authenticate in a highly secure, yet fast, manner.

The GreenRADIUS Premium FIDO Module will add support for the FIDO Ciptor U2F token.

CORE FEATURES

FIDO 1.0 U2F will work with VPN Gateways
Full compliance with FIDO 1.0 U2F specification
Support for FIDO U2F tokens
Self-registration Webpage for easy enrollment
Enables use of 2FA solutions for Access Gateways/Firewall systems with password length limitations
Contact sales to get the GreenRADIUS Premium FIDO Module.

You can learn more about the FIDO here: https://fidoalliance.org/specifications/overview/