When I say this is the most retro digital watch Casio has released in almost 34 years, I'm not kidding. The F-84 has perfect mid-1980s digital styling. It has the older thinner model text, the "Lithium" word to promote the fact it has a lithium battery, and the alarm graphic right below that to promote the fact it has an alarm function.

The quartz movement, designated Module 593 [ citation needed], is powered by a single CR2016 3-volt lithium button cell. [8] Water resistance [ edit ]As mentioned, both have lug widths of 18mm but the ’84’ has a more traditional lug design. With the ’91’, the lugs are pretty much non-existent and should you decide the swap out the straps, it may run the risk of looking a little oddly flush against the case.

Beschizza, Rob (August 14, 2023). "Sensor Watch, a replacement board for the legendary Casio F-91W wristwatch". Boing Boing . Retrieved October 4, 2023. Yeah, it’s true. The ’84’ made its debut in 1986 while the ’91’ was introduced in well… 1991. Although with that said, there are conflicting reports with PacParts stating that the Casio F-91W was born in 1989 instead. Whatever that year may be, the ’84’ is the OG between these two. Combatant status review board for Mohammed Ahmad Said el Edah". The New York Times. October 6, 2004. James Ball (April 25, 2011). "Guantánamo Bay files: Casio wristwatch 'the sign of al-Qaida' ". The Guardian. London.

If anyone knows any other picture of the model F-91 W Japan U, it would be happy and public in this thread. In the F-91 W manufactured in Japan like other models of the F series, such as the F-84w, does not work to apply the right button and see the word CAsio.