Hate the full-body scans, pat-downs and slow going at TSA airport security screening checkpoints? For $100, you can now bypass the hassle.

The Transportation Security Administration is rolling out expedited screening at big airports called "Precheck." It has special lanes for background-checked travelers, who can keep their shoes, belt and jacket on, leave laptops and liquids in carry-on bags and walk through a metal detector rather than a full-body scan. The process, now at two airlines and nine airports, is much like how screenings worked before the Sept. 11 attacks.

To qualify, frequent fliers must meet undisclosed TSA criteria and get invited in by the airlines. There is also a backdoor in. Approved travelers who are in the U.S. Customs and Border Protection's "Global Entry" program can transfer into Precheck using their Global Entry number.

"It's a completely different experience than what you're used to," said Matt Stegmeir, a platinum-level Delta Air Lines Inc. frequent flier who was invited into Precheck when it opened at his home airport, Minneapolis-St. Paul. Besides zipping through security screening quickly and easily, Mr. Stegmeir noticed another difference: TSA agents at the Precheck lane are usually smiling.

"It's really a jarring contrast. It reminds you just how much of a hassle the security procedures in place really are," he said.