The DW-5600C is one of Casio's early G-Shock model watches, being released as a successor of DW5200C "HERO" (the model which boosted G-Shock sales onto the global market). It was manufactured from 1987 through 1996. Many are still in use today. Due to its rugged design (massive machined steel case with a floating module technology kept in place by internal shock buffers, thick mineral glass) capability of operating in high/low pressure environments, a replaceable protective plastic bezel made the design resilient enough to withstand abuse which would destroy more traditional watch designs. In part also due to its dual time, stopwatch, countdown features, and more than 10 years battery life, it is one of the few watch models and the first in the Casio's G-shock product line to be flight-qualified by NASA for space missions. It is also a Hollywood star, being worn by celebrities in action movies (most notably by Keanu Reeves in the film Speed). The letters "DW" stand for "Digital Water resist". This model has become something of a collectors' item among G-Shock aficionados.
Like its immediate predecessors, but unlike most newer models, it was cased in a heavy stainless steel screwback "tuna can", the latest model from this family line being the DW-5800C. Current models (except anniversary editions of 5000 series G-Shock) use a resin or composite case, and a stamped metal back held on by tiny screws. There were two variants released, one pre-1989 with an early 691 module and a polished screwback, and 1990-1996 with the 901 module and a machined screwback, the main difference between modules being the battery size compartment. It is believed that the changes which allowed for a more common battery model and the unpolished screwback were intended to reduce the manufacturing costs.
Proof of its success, after 26 years from the release on the market of the original model, the watch continues into production under the following variants:
- DW-5600E direct successor, composite case and Illuminator, and electroluminescent backlight.
- G-5600 Tough Solar.
- GW-5600 Tough Solar and Wave Ceptor.
- GW-M5600 Tough Solar and Multi-band 5 Wave Ceptor.
- GW-M5610 Tough Solar and Multi-band 6 Wave Ceptor.
- G-5600E Tough Solar - a variant of the GW-M5600 without Wave Ceptor(for sale in non-Wave Ceptor markets)
- GW-5000 Tough Solar, Multi-band 6 Wave Ceptor and stainless steel screwback.
- DW-5600VT Limited Edition series includes Star Wars Darth Vader, Atmos, RX-78-2 Gundam and many others manufactured in quantities as little as 1000.
- GW-S5600 Tough Solar, Multi-band 6 Wave Ceptor, Carbon Fibre strap and stainless steel replaced by Titanium Alloy.
- GB-5600AA Bluetooth.
- Time display in 12-hour or 24-hour format. In regular timekeeping mode, the current home time is displayed to the second, along with the month, date, and day of the week, without any button presses.
- Auto-calendar correctly calculates month lengths, leap years and days-of-the-week between 1985 and 2029.
- Alarm: One alarm. An unusual feature is that in addition to the hour and minute, a month and/or date may optionally be set, so the alarm will only sound during the specified month or on the specified day of the month.
- Time signal (hourly chime.)
- Dual time: Hours and minutes can be set separately for a second time zone (seconds are synchronized with the home time.) The current home time is also displayed in dual time mode.
- Countdown timer: Can be set for any duration from one second up to 24 hours, in one-second increments; optional auto-repeat function. The current home time is also displayed in countdown timer mode.
- Stopwatch: 1/100th second, with one split; rolls over at 24 hours.
- Illumination: Backlight is via a tiny incandescent bulb at the left edge of the display.
- Reminder mark: A peculiar feature seldom seen on newer watches, this is a user-enabled display flag which slowly blinks in all modes. It has no function except to serve as a visual reminder to the wearer.
- Shock-resistant design, intended to survive a 10-meter fall.
- Water resistant to 200 meters.
- Battery: One lithium button cell, CR2320 in older models (module 691) or CR2016 in newer models (module 901.) Either was expected to last ten years or more.
- Official Casio website
- Instruction manual — requires Adobe Reader, free download from Adobe
- Casio G-Shock Forum
- Blog bringing the news in the world of G-Shock
- Unbreakable: Carlos Perez article on early G-Shock models
- DW-5600 Model Versions - The First Nine - An Illustrated Guide