The WORKS℠ is only exclusively available at the initial time of your booking at flyfrontier.com and is not available from third parties. By bundling all the travel extras you get the best value!
The PERKS℠ is available after your initial booking and can be added even if your flight was purchased from a third party. You can also add it when checking into your flight. This bundle does not include refundability or change flights like the WORKS℠.
Learn more here.