this does work however some of the buttons stick and need a little help to return, I'm assuming they need cleaning or lubricating so this is sold as SPARES AND NOT WORKING. The Vintage Bell Punch Plus Sumlock Mechanical Calculator Adding Machine No.509/S866 is a rare and sought-after piece of scientific collectable from the United Kingdom. Dating back to the 1950s, this calculator/adding machine is a testament to the era of mechanical computation. With its intricate design and historical significance, this vintage piece is a valuable addition to any collection of scientific memorabilia.
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