CHICAGO – The neon green fanny pack strapped around Annabel Hess' skinny jeans carried all the essentials for a music festival: credit card, driver's license, phone, Chapstick.

And her passport.

The 25-year-old concert-goer wasn't headed out of the country after Miranda Lambert closed the first night of the annual Country LakeShake festival. She brought it to sign up for TSA PreCheck, the government's expedited airport security program.

Hess, a regular traveler, had been meaning to sign up so she no longer has to beg other passengers to cut the security line when she's running late for her flight. Her roommate has had PreCheck since college and saw the festival's pitch about enrolling on-site and getting a fast pass through festival security as a bonus.

"This was an easy opportunity,'' Hess said. "So here I am.''

She signed up inside the green and purple Identogo RV outside the festival gates in about 10 minutes and headed for the fast-pass line to get into the festival.

Identogo by Idemia, which handles TSA PreCheck enrollment under a government contract, has been trying to boost PreCheck enrollment by offering sign-ups at nontraditional locations. Most people sign up at an airport or a universal enrollment center run by Idemia. In addition to music festivals, Identogo has expanded enrollment to office supply retailer Staples and sporting events including, beginning this year, Boston Red Sox games at Fenway Park.

"What we're trying to do is make it more convenient for people to enroll,'' said Charles Carroll, senior vice president at Idemia. "Take away all the friction points.''

PreCheck sign-ups began at festivals a few years ago in a partnership with concert promoter LiveNation and have been ramped up this year, with LiveNation and at other events, he said. The RV was parked at the BottleRock Napa Valley musical festival in northern California in late May and spent the first weekend in June at CMA Fest in Nashville, Tennessee.

Angie Hamblen, senior manager of marketing and event promotions for Idemia, oversees the PreCheck RV at events around the country. She said the mobile enrollment centers fielded a lot of questions about what PreCheck is in the first few years, but now people are familiar with it.

"Now it's, 'How do I do this? How do I sign up?'''

In a one-hour span at the LakeShake festival, 10 concert-goers filed into the RV to sign up, including a mother and her two daughters and the wife of a frequent flyer who already had PreCheck.

The festival sign-up lineup continues in mid-July with the Forecastle music festival in Louisville, Kentucky. This fall, concert-goers will be able to sign up for PreCheck at Moon River Festival in Chattanooga, Tennessee; Music Midtown in Atlanta and Voodoo Music + Arts Experience in New Orleans.

Carroll said the nontraditional venues tend to draw more vacation travelers to PreCheck, compared with frequent business travelers at airport locations. Festivals also help to draw in millennials, such as Hess and Kate Hansell, a 28-year-old Chicago resident who also enrolled at LakeShake.

Hansell, who has attended the three-day festival ever since it debuted five years ago, travels a few times a year and was tired of being stuck in the standard TSA line at the airport.

"People I travel with all seem to have it, and they seem to get through faster than me,'' she said.

Hansell completed the online application for PreCheck earlier this year, but the closest enrollment center to her office had closed. Members have to visit a center for a background check and fingerprinting.

When she heard about sign-ups at LakeShake ⁠– the festival promotes the program heavily as part of Identogo's sponsorship ⁠– she decided to bring her passport and sign up.

She was approved a week later and used the PreCheck lane at O'Hare International Airport on Friday.

Where can I find a mobile enrollment center for TSA PreCheck?

Identogo has a schedule of the mobile enrollment RV stops on its website. Information about enrolling at Red Sox games is also online. Rather visit a Staples? Identogo has a list of stores currently offering the service.

Do I need to do anything beforehand?

You can make an appointment and fill out the PreCheck application online, but neither is required.

What do I need to bring to the enrollment center?

Proof of citizenship, such as a U.S. passport or a birth certificate, a driver's license and a credit card to pay the $85 enrollment fee. The PreCheck membership is for five years.

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Is it more expensive to sign up at a festival or sporting event?

No.

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I already have TSA PreCheck, can I use the fast pass lane at participating music festivals, Red Sox games and other events?

Yes, but you'll need to bring your known traveler number (KTN) with you to receive a bracelet.

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