Double-Stacking

When both of a team's cars need to stop in the same window, most often right after a Safety Car or Virtual Safety Car has bunched up the field and made a stop cheap, the team can bring them in a lap apart rather than waiting. That's a 'double stack'.

The second car peels into the box right after the first, but has to wait for that first car's tyre change to finish before its own crew can get to work. That wait costs the second car a little extra time next to a stop taken on its own, since the crew and equipment can only service one car at a time.

Even with that extra cost, banking both stops while the whole field is running slowly is usually worth far more than sending one car out to pit alone later, back into a track that's up to speed again.