CHICAGO (CBS)– Between Tuesday and next Monday, nearly 2 million people are expected to travel through O’Hare and Midway airports.

That’s up about 2% from last year.

Sunday will be the busiest day, with a combined 325,000 travelers expected at both airports.

And just in time for the holidays, a faster security process is debuting.

It’s called “Clear” and it verifies your identity with the tap of a finger or the blink of an eye.

“Clear” begins Tuesday at O’Hare Terminal 1. It will eventually expand to Terminal 2.

“Clear” requires a paid membership, and you have to sign up before you can use the system.

“Clear” is available at all of United’s hub airports and at other major airports including Newark, Atlanta and Orlando.

Full membership is $179 a year.

TSA pre-check also offers expedited security screening for $85.