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G-Shock G-STEEL GST-B300 with Front Button

G-Shock G-STEEL GST-B300: GST-B300-1A GST-B300S-1A GST-B300SD-1A

Casio announced the G-Shock G-STEEL GST-B300, and other media outlets have reported on three debut models.

The analog-digital GST-B300 looks like a combination of the GST-B100 (case) and GST-B200 (dial) and has a more traditional, armored G-Shock appearance than the sleeker GST-B200. It is also the first G-STEEL model with a front LED light button. Like the GST-B200, the GST-B300 is a Carbon Core Guard model with a carbon fiber reinforced case and an STN LCD display. The carbon fiber reinforced resin also extends to the front and side button guards. The GST-B300 has Tough Solar power and Bluetooth smartphone link, the signature features of GST-BXXX models.

Other features include world time, 1/1000-second stopwatch, 1/10-second countdown timer (24 hours max), 5 multi-function alarms (with daily, 1 time, schedule), and full auto double LED lights (Super Illuminator) with adjustable afterglow. The GST-B300 measures 51.0 x 50.0 x 15.5 millimeters. (For comparison, the GST-B100 measures 58.1 x 53.8 x 14.1 mm and the GST-B200 measures 53.3 x 49.2 x 14.5 mm, so this puts the GST-B300 more in line with the size of the GST-B200.) GST-B300 models have bands with a quick-release slide lever.

The debut models (pictured in the photo above) are the GST-B300-1A (black resin bezel and black soft urethane band, 82 grams), GST-B300S-1A (silver stainless steel bezel and black soft urethane band, 91 grams), and GST-B300E-1A (silver stainless steel bezel and stainless steel band, plus soft urethane and cloth bands, 185 grams with stainless steel band).

The Japanese model names and retail prices (including tax) are GST-B300-1AJF (44,000 JPY), GST-B300S-1AJF (49,500 JPY), and GST-B300E-1AJR (63,800 JPY). The series is expected to be released in June 2020.

Another model was also reported, the GST-B300SD-1AJF (55,000 JPY), which has a stainless steel bezel, standard (non-inverted) LCD display, and stainless steel band, but this is possibly a later release.

G-Shock G-STEEL GST-B300-1A

Black resin bezel and black soft urethane band.

G-Shock G-STEEL GST-B300-1A


Silver stainless steel bezel, standard LCD display, and silver stainless steel band.


G-Shock G-STEEL GST-B300S-1A

Silver stainless steel bezel and black soft urethane band.

G-Shock G-STEEL GST-B300S-1A

G-Shock G-STEEL GST-B300E-5A

Silver stainless steel bezel with three interchangeable bands included: stainless steel, black soft urethane, and beige cloth.

G-Shock G-STEEL GST-B300E-5A GST-B300E-5AJR with interchangeable bands

G-Shock G-STEEL GST-B300 Promo Video:

G-Shock G-STEEL GST-B300

Sources: www.casio-watches.com, news.mynavi.jp, headlines.yahoo.co.jp

First Post (March 6, 2020):

A Casio UK video from the latest Casio product exhibition in Japan is full of easter eggs that obsessive G-Shock fans have been eating up. Near the end of the video, a large sign displays what appears to be a new G-Shock G-STEEL model.

We are confident that this model is the upcoming GST-B300. Part of what looks like the G-STEEL logo can be seen on the right of the sign, and the watch appears to have a similar dial as the GST-B200, but with a numerical 12 o’clock marker. The bezel and case look more like the GST-B100. This leads us to believe that this model is possibly not a Carbon Core Guard model like the GST-B200. The GST-B300 will have Bluetooth connectivity, and probably Tough Solar power and similar internal functions as the GST-B200.

G-Shock G-STEEL GST-B300

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