Kendall Jenner and Paris Jackson are model pals.

Kendall, 21, was snapped shopping with 18-year-old Paris Jackson at a flea market in Los Angeles on Sunday, where the two enjoyed hunting for vintage finds. "The girls seemed very comfortable with each other -- joking around and talking a lot while shopping for records," an eyewitness tells ET. "They were hanging out like best buds."

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Kendall, clad in a lime green sweater and jeans, seemed enamored with a forest green hat, which she tried on.

Interestingly enough, Paris -- rocking ripped jeans and a thermal -- checked out a Michael Jackson "Thriller" colored vinyl, but ended up passing on her late father's record and buying a Beatles one instead.

The eyewitness tells ET that the pair spent about an hour and a half together before leaving in separate cars, and that Kendall also purchased a few home decorative pieces from a print maker.

Kendall and Paris' friendship goes way back. In an April 2015 GQ interview, Kendall talked about visiting the late King of Pop's famous Neverland Ranch growing up. "I remember going, actually, and as I was leaving, Michael Jackson was coming in," she recalled to the magazine. "And I was like, 'Oh, my God! That was Michael Jackson!'"

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More recently, Paris was front row at Givenchy's menswear fall/winter 2017-2018 show at Paris Fashion Week in January, where Kendall walked the runway.

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