CASIO Blood Pressure Monitor BP-100
This is Casio's 1st generation of the blood pressure monitor watch.
The accuracy of the readings depend very much on the initial data you key in. Of course, I couldn't be bothered with all the functions! What attracts me most is the large screen and stainless steel caseback of this early Casio. This is an early Japan made new-old-stock manufactured in 1990 and the style adopted is consistent with early Casio design e.g. it uses the conventional small light bulb at the side for reading in the dark. The black resin strap is flexible yet extremely durable and I remembered my first watch was a Casio and it took a lot of beating to get the strap to break finally!
An interesting writeup of this watch can be found here. Scroll to the end to download a PDF version of the instruction manual. (Courtesy of gafortiby.com)