In 1974, Casio borrowed its calculator division’s LSI tech in order to deliver the world’s very first digital watch with an automatic calendar function. Christened the “Casiotron,” the watch was able to track seconds, minutes, and hours, along with displaying the month, date, and day of the week — plus automatically adjusted for the year’s shorter months. Upon its release, the Casiotron was a bonafide luxury item, costing just shy of an average month’s salary, or the equivalent of ¥58,000 (~ $369 — or $2,350 when adjusted for inflation today). 

With half-a-century having passed since its debut, the Japanese brand has now opted to celebrate the 50th anniversary of the Casiotron’s release with a limited edition run of special Casio 50th Anniversary Sky and Sea Series watches. 

The Basics 

Taking inspiration from Casio’s “Sky and Sea” concept, this entire 50th anniversary series sees each watch decorated in a sky-inspired blue and sea-inspired gold colorway. The anniversary collection is comprised of the G-SHOCK GMW-B5000SS-2, the Edifice ECB-2000SS-2A, and the PRO-TEK PRW-61SS-2. Anchoring the collection is the modernized Casiotron TRN-50SS-2A — though five-watch collection also includes the solar-powered BABY-G BGA-S290SS woman’s watch. 

G-SHOCK GMW-B5000SS-2

The latest addition to the 5000 Series lineup, the G-SHOCK GMW-B5000SS-2 is a full-metal digital watch design that’s based on the GMW-B5000 but sees the timepiece bestowed with a host of updated elements and nods to the original Casiotron. Made in Japan, the watch boasts a bare alloy finish that’s been scented via a blue bezel and a gold inner bezel and buttons. In addition to a screw-lock case-back decorated via Casio’s 50th Anniversary logo, this Sky and Sea series model also gets a fluted design that pays homage to the Casiotron from ’74. 

Edifice ECB-2000SS-2A

Based on the Edifice lineup’s suspension arm-equipped ECB-2000 SOSPENSIONE, the Edifice ECB-2000SS-2A is an elegant take on a premium race-inspired watch that adopts the Sky and Sea color scheme. Loaded with Bluetooth connectivity and solar time-keeping, the watch features a 51mm L × 47.8mm W × 10.8 mm H case made from a combination of carob fiber and stainless steel. Water resistant down to 100 meters, the ECB-2000SS-2A also features a case-back decorated in a 50th Anniversary logo, and a blue Alcantara strap. 

PRO-TEK PRW-61SS-2

Starting with the existing PRW-61, Casio has delivered the Sky and Sea Series PRO-TEK PRW-61SS-2.  Equipped with solar charging and 100 meters of water resistance, the watch consists of a 47.4mm case with a blue IP bezel that’s laser-etched with a fluted pattern, plus a dial ring decorated in a gold-hued glass vapour deposition and gold-color accents on the inset dial ring and crown. The watch’s case and case-back — the latter of which sports a 50th Anniversary logo —are both crafted from bio-resin. The PRO-TEK PRW-61SS-2 also comes mated to a flame-retardant cloth  band that’s composed of recycled PET. 

Casiotron TRN-50SS-2A

Headlining the 50th Anniversary Sky and Sea Series is Casio’s Casiotron TRN-50SS-2A. Maintaining the original watch’s iconic fluted pattern and auto calendar function, the watch is made in Japan and is constructed around a 42.7mm L x 39.1mm W x 12.3mm H stainless steel case sporting a blue bezel and dial and gold-finished buttons, a gold inner bezel, and a gold display surround. Paired with a matching stainless steel bracelet, the TRN-50SS-2A also gains modern Bluetooth connectivity and a solar-powered battery. The back of the new Casiotron comes capped off with a stainless steel case-back with a blue-toned glass insert adorned in a special 50th Anniversary logo. 

What Makes Them Special

Every watch in this limited edition lineup not only sports a special blue and gold color scheme, but they also all manage to pay homage to the original Casiotron with their use of its iconic fluted pattern. The use of special materials and the unique 50th anniversary logo on the case-back of each timepiece further separates that from their non-limited-edition counterparts. Additionally, Casio clearly selected a diverse range of watches to bestow the Sky and Sea treatment onto, though it’s clear each watch boasts features and tech that’s in line with the spirit of innovation that lead to the creation of the original Casiotron some 50 years ago.

Pricing & Availability 

The Casio 50th Anniversary Sky and Sea Series watches will be available starting in June, though thus far this release is limited to Casio’s native Japanese market. Prices for the watches have yet to be announced.

Casio 50th Anniversary Sky and Sea Series Watches

Casio marks half-a-century since the original Casiotron’s debut with a limited edition run of commemorative Sky and Sea Series G-SHOCK. PRO-TEK, Casio, and Edifice watches.