The hp-01 was introduced by Hewlett-Packard in 1977 and was the first digital wristwatch with an integrated scientific calculator. It was developed by the hp Advanced Products Division - many engineers from the field of calculator development were involved. The watch was a prestige object and was designed specifically for executives, technology enthusiasts and professionals. Due to its complexity and price (650-850 usd - around 3,000-4,000 eur adjusted for inflation), it was not a mass product. hp produced around 12,000 pieces, of which around 8,000 were in stainless steel and 4,000 in gold-plated stainless steel. It was a symbol of hp's pioneering technological spirit, but was withdrawn from the market as early as 1979 because it was far ahead of its time and the market was not yet ready for it. The hp-01 was a masterpiece of microelectronics: Display: LED display (red) activated by pressing a button (to conserve battery power) Functions: Time, date, alarm, stopwatch, calendar functions, scientific calculator (trigonometry, exponential calculations, memory functions) Buttons: 28 small gold or stainless steel buttons that were precisely operated with a stylus (which was integrated into the wristband) Calculation accuracy: 10 digits (in calculator mode) Memory: 3 registers with 10 digits each Power supply: Three silver oxide button cells Scope of delivery: The scope of delivery includes the watch: the original box the original manual in English and a German copy the original pen the original brochure the original envelope with the service letter the original stylus which has its place in the bracelet.