An original Apple-1 PC is due to go under the hammer at London auctioneer Christie's in October — where it is expected to fetch a minimum of £50,000.
The device, with the serial number of 22, was — like the rest of the Apple-1 line — designed and built by Steve Wozniak while Steve Jobs took care of sales and marketing.
"This is the computer that started Apple, now recognised as the most valuable company in the world; its significance in making computer technology accessible for all cannot be undervalued," James Hyslop, scientific specialist at Christie's, said in a statement on Monday.
The device, from the estate of former Apple employee Joe Copson, is expected to reach a final selling price of between £50,000 and £80,000.
In December 2011, Copson's Apple-1 was put on eBay with an initial starting price of $170,000 (£107,000) but failed to sell. When it first went on sale in 1976, the Apple-1 had an asking prices of $666, although it was later reduced to $475. Until the model was discontinued, around 200 Apple-1s were sold.