All those interested in owning a piece of Apple history, listen up.

According to a news report published by the Associated Press on Friday, one of the first Apple computers ever built is going to be offered on Christies as an auction item starting this week. The computer, supposedly designed, built, and sold out of the garages of Apple founders Steve Jobs and Steve Wozniak, is a historic “Apple 1,” a 1976 model that served as the company’s humble beginning. Today, Apple rules the world of electronics, with products like the Macbook, the iPad, the iPhone, and the iPad in consistent and high demand, and the Apple 1 was the first step Jobs and Wozniak made toward those innovations.

Due to its historical value, experts say the computer could be worth more than half a million dollars. Christie’s certainly must believe it’s somewhere close to that: the international auction house is starting the bidding for the item at $300,000, and bids are expected to escalate quickly.

The current owner of the Apple 1, a 70-year-old retired school psychologist named Ted Perry, agrees with the assessment that a certain amount of milestone significance exists in the dusty and clunky old computer, which has apparently been sitting in a cardboard box at his Sacramento home for years.

“This is a piece of history that made a difference in the world,” Perry said. “It’s where the computer revolution started.”

Perry can’t recall precisely when he came to own the Apple 1–probably in either 1979 or 1980–but he does remember that he paid nothing for it. The computer passed into his ownership as a secondhand swap with the owner, another California resident who had advertised the model in a local newspaper. Now, Perry is looking to cash in big time on that modest trade.

The Apple 1, a green, 11-by-14  hunk of plastic with a messy array of memory chips and wires sticking out in every direction, kicked off Jobs’ and Wozniak’s vision. The two manufactured about 200 models of the computer, which boasted eight kilobytes of memory and retailed for $666.66, but experts estimate that only about 30 or 50 still exist, making auctions like this one global events for tech enthusiasts. Just last month, another Apple 1 sold in Germany for $671,400.

Perry and a Christie’s-hired expert have made sure that the computer in question is still operable, and Perry assured potential buyers that the model” still works,” and with “the original chips,” no less.

Perry’s Apple 1 will go on sale as part of Christie’s tech-specific auction block, “First Bytes: Iconic Technology from the Twentieth Century,” between June 24 and July 9. In the meantime, the computer will be displayed at the Computer History Museum in Mountain View, California.