An unopened cardboard box filled with packs of hockey cards from 1979 to 1980 sold for a whopping sum. $3.72 million At auction on Sunday, according to Heritage Auctions.

There are 16 boxes of cards in the carton, each filled with 48 packs of O-Pee-Chee hockey cards, according to a press release from the auction house.

The heritage auction house said the box may contain two dozen Wayne Gretzky cards from his early years. Gretzky, known as one of hockey's all-time greats, was playing for the Edmonton Oilers at the time the cards were printed.

“We knew from the moment we heard about the O-Pee-Chee case that it would attract the attention of hockey card collectors around the world,” said Chris Ivey, director of Heritage Sports Auctions.

The box of cards was originally owned by a man who was a “rabid collector” in the 1960s and 1970s, according to Heritage Auctions.

“Remarkably, our addressee was unaware that he was in possession of this atrocious Holy Grail bag until a long-forgotten pile of boxes was registered at his home in Saskatchewan,” Heritage Auctions wrote in the item description.

Jason Simmonds, a sports card specialist and shipping manager, said the man's son found the case behind “piles and piles of other stuff.”

Heritage Sports said there were 10,752 “factory fresh” cards inside the box, which were verified prior to the auction.

According to Heritage Auctions, no other unopened case of O-Pee-Chee cards from 1979 to 1980 has appeared in the 21st century.

“By any measure of evaluation, it is a sensational miracle of survival, and one of the greatest trading card sets that Heritage has ever had the honor of offering.” Heritage Auctions He said.

The auction house did not reveal the identity of the buyer.