Certificate sets are required to generate Apple Passbook passes. They are used to sign and encrypt the pass data. We have a default certificate set that you are able to use for testing purposes. However, you will need to create your own certificate set for production use.
New certificate sets can only be created in the dashboard. To create a new certificate set, navigate to the certificate sets page and click the “Create new certificate set” button. There you will also find a guide on how to create one. Please note that you will need to have a valid Apple Developer account.
When creating a new iOS pass template, you will be able to select your certificate set. If you have not created a certificate set yet, you will only be able to select the default certificate set.