[He hands up the vent cover, releasing it when he's sure the other man has a grip, then waits for his hand to descend once more. When it does he jumps up, grabbing hold and pulling just enough to get his free hand up to the vent opening which he grips firmly, grasping with his other hand after a moment. He gives the Brit enough time to shimmy out of the way, then pulls himself into the vent the rest of the way, his wide shoulders making it a tight squeeze.]

I got the bolts, gimme a sec. [He quickly inserts them back into the vent cover, moving slowly so the entire ventilation system won't come crashing down around them, and so it hopefully won't get too...noisy.

After that is done, he takes in a few deep breaths, then nods past Jack.]

That way's where the air is coming from.