Casio Blog – 2.14.18
The G-Shock Mudmaster GSG-100 series is basically the same as the Mudmaster GWG-100 series released in Japan and China, only without the Multi-Band 6 radio time syncing feature. The GSG-100 is similar in size to the Mudmaster GG-1000 Twin Sensor non-solar model and a little smaller than the original Mudmaster GWG-1000 Triple Sensor model.
Read more: G-Shock Mudmaster GSG-100 Series with Tough Solar