When the adjustments are finished, the bottom left button can be pressed once to return the watch to normal mode. After 30 seconds it will start the next minute as displayed. Should this happen before 30 seconds, the watch will zero in at the beginning of the current minute. Unlike any other value, the seconds can only be zeroed. The right button is used to adjust the flashing value displayed. The top left button is used to cycle through seconds, hours, minutes, month, date, day, and normal mode. The time or date is adjusted by pressing the lower left button three times to bring the watch to time adjustment mode. Pressing all three buttons at the same time will fill all the cells on the LCD until any button is pressed again. The right button, labeled "Alarm On-Off/24hr", is the function button: when used, it starts and stops the stopwatch, changes the settings currently being adjusted, or switches between the 12- and 24-hour modes, depending on what mode the watch is currently in.The lower left button, labeled "Mode", cycles the modes of the watch: time display, alarm, stopwatch, and time/date adjustment.
The upper left button, labeled "Light", turns on the light, cancels the alarm, resets the stopwatch or marks the split (lap) time, and is used for selecting settings.The watch is controlled by three side-mounted push-buttons. The watch is currently set to sound the alarm and hourly chime NOT suitable for showering, bathing, swimming, snorkeling, water related work and fishing".Ĭasio F-91W, in regular timekeeping mode and using the 24-hour display option.
100 feet / 44 psi), the ISO standard meaning of which is: "Suitable for everyday use. The black version (F91W-1) is "30 meter / 3 bar" (i.e. The watch front is marked " Water Resist", but Casio reports different values for different variants of the watch. The quartz movement, designated Module 593, is powered by a single CR2016 3-volt lithium button cell. According to manufacturer estimates, the watch is reported to be accurate to ☓0 seconds per month. The watch uses a faint, green LED backlight located to the left of the display for illumination (in earlier versions it was an amber microlight).
Other features include an hourly time beep and a single daily alarm lasting 20 seconds and an annual calendar, with adjustment for leap years not supported as the watch does not record the year. The stopwatch also has the feature to mark net and split time (lap). The F-91W is a chronograph, featuring a 1⁄ 100 second stopwatch with a count up to 59:59.99 (nearly one hour).
The resin strap is 18 millimetres (0.71 in) at the fitting and 22 mm across the widest part of the lugs. The case is primarily made of resin, with a stainless steel caseback and buttons with the manufacturer's module number, 593, stamped on the caseback. Designed by Ryusuke Moriai as his first design for Casio, the case of the F-91W measures 37.5 by 34.5 by 8.5 millimetres (1.48 by 1.36 by 0.33 in).