There is two type of EMD:
EMD-A - Document that allows for the fulfillment of all flight related services and fees (such as bags, seats, meals, etc.). An EMD or EMD-A is linked to a specific eticket coupon in the airline’s database.

EMD-S - Non-flight related services (such as lounge access or change fee collection) a stand alone EMD, a EMD-S is issued. To issue an EMD-S a manually created service segment must be in the PNR. Specific services that can be charged on an EMD-S is dependent on the airline’s own requirements.