QUEENS, N.Y. - It's an elite team with international members. You have to be meticulous, consistent and most of all, fast.

No, not the tennis players. We're talking about the racket stringers. 

"It just never gets old, seeing my work on the court. Whether it's seeing a 10 year-old playing with a green dot ball or whether it's the highest level of our sport," said Mike Stephens, a stringer.

Stephens is one of 21 stringers representing 11 countries at the US Open. Throughout the tournament, the elite team will string racquets more than 5,500 times. Sometimes more than 500 in a single day. 

"There's a buzz to it. There's a little adrenaline rush," said Joe Heydt, a stringer.

That's part of what keeps Heydt, a Nebraska native, coming back every year. This year is his 11th US Open. He compares stringing racquets to being a chef — each player has a particular recipe to follow.

"They know exactly how they want that food to taste. And we have to make it consistently each time," he noted.

"The racquets are customized to their feel, to their grip and then their strings are customized to their game. So the tensions change, the patterns change, the strings change. All to fit their game the best," Stephens explained.

The work is hard, the days are long (you're always on your feet), and the stakes are high. 

An 'on-court' is when a player needs a racquet strung in the middle of the game. The goal is to do it within 12 minutes. 

"We have to string it as quickly as we can. And that's really where it's hard, because you know they're on waiting for that racquet," Heydt said.

Stephens says tongue-in-cheek that stringing racquets is only slightly less stressful than his previous career, a nuclear engineer.

"There's no lives on the line, we're just stringing racquets," he said.

All joking aside, they say some moments make all of the hard work worth it, especially when the opportunity arises to string the racquet of one of the greatest to ever play the game: Roger Federer.

"In my notebook, I wrote down exactly how he likes his racquet strung. Because it's very, very specific. And you don't get to learn that. And you never say that you've strung Federer's racquet unless you've done it," Heydt said.

In the past, the work was done tucked away in a room underneath the stadium. But now the entire team will be on display at the Wilson store throughout the remainder of the tournament.