In the early 1990s, Apple partnered with Adidas to design a pair of chunky white sneakers that featured the word Apple alongside a rainbow-colored Apple logo. According to JustCollecting News, the shoes never reached the market, and it’s believed that the prototypes were sold to Apple employees.

As far as we know, only two pairs exist. One was unearthed in 2016 at a garage sale in Palo Alto, California, and later sold at an auction—and the other one is hitting the auction block next month. iMore reports that the auction will be hosted by Heritage Auctions in Dallas on March 24, but you can submit your bids online starting March 3.

The Adidas sneakers feature a rainbow-colored Apple logo.Heritage Auctions

Though these size-9.5 sneakers aren’t quite as gleaming as brand-new kicks, their slightly worn appearance gives them a classic ’90s charm that many contemporary shoe designers are trying to mimic. It’s not always the look for less—a pair of pre-distressed Golden Goose sneakers, for example, could cost you almost $500.

It remains to be seen just how much money bidders are willing to shell out for these ultra-rare Apple ones, but the popularity of vintage Apple products in general suggests that it could be a considerable sum. Back in 2014, the Henry Ford Museum paid a staggering $905,000 for an Apple Computer 1, though the fact that it was hand-built by Steve Wozniak, one of Apple's founders, no doubt heavily contributed to its appeal.

Adidas sneakers weren’t Apple’s first foray into the world of wearable merchandise. In 1986, just a year after Steve Jobs’s tense exit, the company launched The Apple Collection, featuring popped-collar polos, T-shirts and sweaters emblazoned with Apple in funky, multi-colored lettering, and even the first Apple watch (which cost $35 and only told time). See the catalog in all its retro glory here.

[h/t iMore]