William 'The Refrigerator' Perry's Super Bowl ring being sold at auction

The largest Super Bowl ring ever made is up for auction.

Heritage Auctions is selling William "The Refrigerator" Perry's Super Bowl XX ring to the highest bidder at the National Sports Collectors Convention in Chicago on Thursday.

The ring, made by Jostens, is believed to be somewhere between a size 23 and a size 25, though no measuring tool exists to confirm that fact. The opening where Perry put his finger is said to be roughly the size of a half-dollar coin.

Chris Ivy, director of sports auctions for Heritage, said Perry sold the ring in 2000 to a collector and provided an assurance of its authenticity. In 2007, that collector sold the ring in an auction for more than $27,000, and Ivy said this latest buyer has consigned the ring to the Heritage auction for Thursday's sale. In early bidding on Heritage's website, the ring has already received bids up to $31,070.

Because of the sheer size of the ring, many salesman samples of the Perry ring were produced and sold. In 2011, a 10-year-old named Cliff Forrest Jr. bought a Fridge Super Bowl ring using $8,500 from his college fund money and gave it back to Perry, believing it was the real deal. Attempts to reach the Forrest family for comment were unsuccessful.

Given the low price, collectors at the time had suspicions, as does Ivy, who said the chain of custody from Perry selling his real ring in 2000 through today is impeccable.

As for Perry, he's not so sure.

"What that kid and his daddy brought to me four years ago, I think that was the original one," said Perry when reached by ESPN.com on Wednesday evening. "I had to cut the ring even more in the middle to fit my finger, and that one had the cut in it."

That ring, Perry said, is in a safe-deposit box in Georgia.

The ring being sold by Heritage, the auction house says, is 10-karat gold with genuine diamonds. Salesman samples usually have cubic zirconia stones.