Choices of other Casio models that have the same functionality as the F-91W that have bigger buttons are the W800H, the F105W, and the one I'm talking about that I just bought, the W59. For small-wristed folk such as myself that prefer smaller digital timepieces, the go-to brand is Casio for that sort of thing. And the go-to watch in that brand is, of course, the F-91W.

Just How Water Resistant Is The Casio F91W? | Hackaday Just How Water Resistant Is The Casio F91W? | Hackaday

I don't know exactly when this watch was introduced to market, but it definitely came shortly after Timex released watches with the the Indiglo nightlight technology in 1992. My guess is that at earliest, the F105W is probably a design from the mid-1990s. Is the F105W exactly the same as the F-91W? Water resistance is an important feature of a modern watch. It makes wearing the watch far more practical in this modern world of sudden rainstorms and urban water balloon ambushes. The Casio F91W, one of the company’s most popular watches, is claimed to be water resistant to “30 meters”, which in ISO parlance, means it is suitable for splashes and rain resistance only. [Rostislav Persion] wanted to get a better idea of what this really meant, so set about investigating for himself.In Walmart for example, you'll easily find the F-91W there as well as the F108 and the recently introduced W217 (very similar styling to the F-91W but larger with notably better nightlight.) But both of those models have an amber nightlight that while it does work very well, it's not the cool blue one. While I described the W93H as a bit of a dud for me in my last article, the F105W is a total winner in my book. When you want an F-91W with bigger buttons that are easier to press, this watch nails it. Slim profile, ultra lightweight case, proper beep tone that can be heard easily, and you get slightly better water resistance at 50M instead of the F-91W's 30M. That doesn't count for much, but hey, it has it. Given [Rotislav’s] results, we’d be far more confident getting our affordable Casio watches a little wet. Obviously, we wouldn’t expect to make a warranty claim if damage occurred from use outside the specs, but it’s clear the watch is far more capable than standards might suggest. If that’s not enough though, you can always set about modifying the watch to improve its water resistance even further. Technical amendments and errors excepted. The sizes in figures do not correspond to the original sizes.

casio on Reddit: Possibly unpopular opinion: the F-105 is r/casio on Reddit: Possibly unpopular opinion: the F-105 is

For those not in the know, the F105W is like the F-91W, but with one rather important improvement. The nightlight is a million times better. This is why ILLUMINATOR is so prominent on the watch face. Because of this, it isn’t uncommon to see individual watches exceed their rated pressures, and also to fail well below their rated pressures, even in the same make and model for cheaper watches.. The first step was to simply immerse the watch under 5.5″ of cold tap water while pressing the buttons and observing for any signs of water ingress. Already, the watch proved it is far more than just rain resistant, so [Rotislav] decided to disassemble the watch and learn how it achieved this.On my 6.75" wrist, the F105W lays more flat than the F-91W, which is something I very much appreciate so the watch stays put. Does a nightlight really matter that much? People all over the world love the F-91W because it just works. The only complaint anyone ever has about the F-91W is that the nightlight is terrible. Solution? Buy an F105W. Problem solved. The resin housing is the ideal everyday companion. It is durable, lightweight and relatively insensitive to cold, heat or other external influences. Although I've not tested this, the F105W is supposedly 27g in weight while the F-91W is 20g. I don't feel the 7g difference if there is one, and I don't think anyone else would.