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.. You get a 3 year warranty-certificate for your new timepiece. If there is any problem with the mechanism, this certificate garanties a 100 % protection- meaning we take care of the technical integrity inbetween these 3 years. 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.

Technical amendments and errors excepted. The sizes in figures do not correspond to the original sizes.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.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?

Natural resin is the ideal material for wrist straps thanks to its extremely durable and flexible properties. 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.Resin is made of synthetic resin and is the ideal material for bracelets due to its extreme durability and flexibility. The daily alarm reminds you of events that recur every day, by emitting an audible signal at the set time. 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. Elapsed time, split time and end time are measured with an accuracy of hundredths of a second. The measuring capacity of the watch lasts up to one hour. The time display can be set to 12- or 24-hour format. In 12-hour mode, there is a p in the display for the second half of the day, i.e. 12 noon to 11:59 p.m.

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.

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. 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.