If you can make that admission item its own registration path, you can add the voucher code widget to the path. This will require a code for registration, and the admission item will show as free wherever it appears.
Adding Voucher Codes to an Even
If you don't see the option to add voucher codes to your event, you may need to talk to your account rep. It is a feature that needs to be enabled in your account, though from what I gather from others on the community is included in most base contracts.
Hope that helps!
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Jess Olcott
Training Program Coordinator
ETC, Inc.
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