Casio is releasing a new analog-digital G-Shock G-STEEL series that has the same look and features as the GST-S100 and GST-W100 series but in a smaller mid-size form factor that is about 90% the size of the original G-STEEL. The G-STEEL GST-W300, GST-W310, and GST-S310 have a smaller size of 55.9 x 49.3 x 15.3 mm compared to the original G-STEEL size of 59.1 x 52.4 x 16.1. These models will appeal to those with small wrists or those who prefer a more formal-looking analog G-Shock that isn’t the usual extra-large size. The GST-W300 and GST-W310 models with Tough Solar and Multi-Band 6 automatic time adjustment are likely to be released in Japan and Asia only, but Casio has also announced the Tough Solar-equipped silver GSTS310D-1A with stainless steel band for a U.S. release.
Update: The GST-W300-1AJF, GST-W300BD-1AJF, GST-W300G-1A2JF, GST-W300G-1A9JF, and GST-W310D-1AJF are June 2017 releases in Japan.
Update 2: The GST-S300-1A, GST-S300BD-1A, GST-S300G-1A2, GST-S300G-1A9, GST-S310D-1A are June 2017 releases for the rest of Asia. These watches have Tough Solar power but not Multi-Bannd 6 timekeeping like the Japanese versions. This raises the possibility that more of these mid-size G-STEEL watches may be released in America in addition to the GSTS310D-1A.
Update 3: Along with the stainless steel-banded GSTS310D-1A (list price $350 USD), Casio America is also releasing the blue GSTS300G-1A2 and gold GSTS300G-1A9 with a list price of $280 USD each. These three models are scheduled for a July 2017 release in the U.S.
The G-STEEL line is known for its classy analog-digital design, stainless steel body, and a dual-layer bezel for extra protection. With its mature look, shock resistance, and 200-meter water resistance, The G-Shock G-STEEL line is suitable for both outdoor activities and more formal environments like the office and social functions. With the Tough Solar power system that uses a rechargeable battery, the G-STEEL GST-S310 and GST-W300 are maintenance-free watches that can be worn for all occasions. Other features include neo-brite luminous hands, world time (48 cities + UTC), 1/100 second stopwatch, countdown timer, 5 daily alarms, battery level indicator, and full auto double LED light with afterglow.
GST-S310D-1A: (Silver) Tough Solar, silver body, silver stainless steel band, stainless steel outer bezel. List price $350 USD.
GST-S300G-1A2: (Blue and Black) Tough Solar, blue IP body, black resin band, resin outer bezel. List price $280 USD.
GST-S300G-1A9: (Gold and Black) Tough Solar, gold IP body, black resin band, resin outer bezel. List price $280 USD.
GST-S300-1A: (Silver and Black) Tough Solar, silver body, black resin band, resin outer bezel.
GST-S300BD-1A: Tough Solar, black IP body, black IP stainless steel band, resin outer bezel.
The following models are for the Japanese domestic market. The difference from the previous models is that these models have Multi-Band 6 atomic time syncing.
GST-W300-1AJF: (Silver and Black) Tough Solar/Multi-Band 6, Silver body, black resin band, resin outer bezel. List price is ¥35,000 JPY.
GST-W300BD-1AJF: (Black) Tough Solar/Multi-Band 6, Black IP body, black IP stainless steel band, resin outer bezel. List price is ¥52,000 JPY.
GST-W300G-1A2JF: (Blue and Black) Tough Solar/Multi-Band 6, Blue IP body, black resin band, resin outer bezel. List price is ¥40,000 JPY.
GST-W300G-1A9JF: (Gold and Black) Tough Solar/Multi-Band 6, Gold IP body, black resin band, resin outer bezel. List price is ¥40,000 JPY.
GST-W310D-1AJF: (Silver) Tough Solar/Multi-Band 6, Silver body, silver stainless steel band, stainless steel outer bezel. List price is ¥45,000 JPY.