hp 25 00hp 25 01Model: HP-25
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Year: 1975/1978
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Info: The HP-25 was a hand-held programmable scientific/engineering calculator made by Hewlett-Packard between early January 1975 and 1978. The HP-25 was introduced as a cheaper (US$195 MSRP) alternative to the ground-breaking HP-65.

 

WIkepedia HP-25