The so-called "combo card" combined two identity cards of importance to non-citizens in the United State: an Employment Authorization Document (also known as a work permit or EAD) with Advance Parole permission (allowing people to travel and return to the U.S. without abandoning their green card application-in-progress.) The net result was that recipients didn't need to carry around two separate items. (The EAD was always a plastic identity card, while Advance Parole permission formerly came as paperwork.)
However, in 2022, U.S. Citizenship and Immigration Services (USCIS) stopped issuing this type of card. Please regard the below discussion as largely historical.
The convenience of consolidating these two items didn't come with much in the way of other benefits to the recipients. In particular, it:
Applicants who submitted separate applications for an EAD and for AP needed to include two identical, passport-style photos with each application. These usually needed to be professionally done, in order to meet the size and other requirements. But when filing the two applications concurrently for the combo card, applicants needed to provide only two photos.
Once issued, the combo card typically last one or two years, depending on what USCIS decided. That gave plenty of time for USCIS to make a decision on the green card application (unless, of course, the per country limitations (quotas) delay application processing).
Once you have a U.S. green card, you will not need a separate work permit, nor will you need advance parole in order to travel.
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