Zulu 1 is a fire team of Zulu Squad encountered in Spec Ops: The Line.
In The Line[]
Following Delta Squad's assault on the Trans-Emirates Building, and subsequent hijacking of the radio tower there, Zulu 1 was sent to the tower, along with Zulu 2 and numerous other 33rd soldiers, in hopes of eliminating the Delta operators.
When Delta descends from the radio tower, Zulu 1 is already preparing to breach the door. Walker and Adams lay in wait on the other side, and promptly eliminate the team when they enter the building.
It's not known if they actually used one, but the breaching sound of the door bears an extremely similar sound to a sticky grenade fuse going off. If so, this would mark the only time a sticky grenade is used by the 33rd.