HK 49

These are confirmed, one-way, North American electronic certificates that are given to 1Ks and UGS every quarter provided they fly 10,000 miles (each quarter). Unlike the 500-mile upgrades, these can be confirmed at the time of booking--it's not necessary to wait for the 100,72, and 48 hour windows.

UGS

United Global Services

This honorary distinction is awarded to UA's highest revenue-generating customers. It's a step above 1K. Just because you're UGS doesn't necessarily mean you fly 100K (or more) with UA on an annual basis.