Casio F-91W-1

The Casio F-91W-1 is legendary for its impressive battery life, typically lasting up to seven years on a single CR2016 lithium coin cell battery. This longevity is a major reason why the watch has maintained its immense popularity since its launch in 1991.

Yes, the digital watch is water-resistant up to 50 meters, which Casio denotes as "Water Resistant 5 BAR". This means it can easily withstand accidental splashes, rain, and even showering, but it should not be used for scuba diving or snorkeling.

Despite its incredibly low price, the F-91W features a daily alarm, a countdown timer, and a 1/100th second stopwatch. The digital display also includes an auto-calendar, a backlight for checking the time in the dark, and the option to toggle between 12-hour and 24-hour formats.

Beyond being a budget staple, the watch has gained a cult status and is instantly recognizable by its blue face and rubber resin strap. It notably gained notoriety for reportedly being used as a timing device in improvised explosive devices by militant groups in the 1990s and 2000s.