DW-5600UE-1ER

The DW-5600UE is the current production version of the square that started it all. The case shape is untouched, which is rather the point — Casio has never had a good reason to change it.

What did change is the light. Where the long-running DW-5600E used an EL backlight, the UE moved to a white LED, which Casio calls Super Illuminator. The dial says so: LED BACKLIGHT is printed right below the display. It is brighter, more even across the LCD, and does not dim with age the way EL panels tend to.

The other meaningful change is battery life. Casio quotes approximately five years on a CR2016, against roughly two for the older module. Same cell, better efficiency.

Under the bezel it runs module 3525 — not the 3229 of the DW-5600E. Worth knowing if you are cross-referencing manuals or ordering a replacement part.

Everything else is the square as you remember it: 200 m water resistance, mineral glass, a 1/100-second stopwatch, 24-hour countdown timer, multi-function alarm with flash alert, and a full auto-calendar to 2099. It weighs 52 g and measures 48.9 by 42.8 by 13.4 mm, which is small by modern G-Shock standards and part of why it still works on almost any wrist.