Computer Know-How section of the store", alongside computer software and blank cassette tapes. The ZX81 would be sold in 112 stores around the UK and would serve as the centrepiece of the "Computer Know-How" sections. Selling the ZX81 over the counter was seen as something of a gamble and Rowland's colleagues were initially unenthusiastic about the scheme. Branch buyers thought that the ZX81 was unlikely to sell more than 10–15 units per branch at launch. Rowland himself thought that the ZX81 would sell about 10,000 units during the first five months of the retail agreement, equivalent to one month's mail order sales by Sinclair. In the event, the ZX81 was a massive success for Smith's, it went on sale for making it the first home PC in the UK to retail for under . The "Computer Know-How" sections were swamped with eager customers, overwhelming the 300 staff who had been trained to demonstrate the machines; a Financial Times correspondent wrote of being "dazed and bewildered by the crowds of schoolchildren clustered round the ZX81 in your local branch of W.H. Smith." Within a year, Smith's had sold 350,000 ZX81s, making an estimated net profit of . Sales of peripherals, software, books and magazines netted even more profit. The British chain stores Boots, John Menzies and Currys began selling the ZX81 as soon as Smith's exclusive distribution deal expired and a number of companies secured overseas distribution rights for the ZX81, which was being sold in 18 countries by March 1982. Sinclair launched the ZX81 in the United States in November 1981 at a price of assembled and in kit form, initially selling directly to the American market by mail order. To be useful the computer needed an extra RAM pack which cost . Sales reached 15,000 a month by January 1982, while American Express sold thousands more to its own customers. In February 1982 Timex obtained a licence from Sinclair to sell the ZX81 directly through thousands of retail outlets in the US, paying Sinclair Research a 5 per cent royalty on all Sinclair hardware and software sold by Timex. The company was later to produce its own licensed clones and variants of the ZX81. By August 1982 Sinclair had lowered the American mail-order price of the assembled ZX81 to and kit to , and its advertisements stated that "more than 10,000 are sold every week". In December 1981 Mitsui