CASIO G-SHOCK - The G-SHOCK GRAVITYMASTER GR-B100. Equipment for pilots, connects to your smart phone for flight log information. https://products.g-shock.com/asia-mea/en/_detail/GR-B100-1A2/ | Facebook
Casio Gr-B100-1A3Jf G-Shock Gravitymaster | eBay
Casio G-Shock GR-B100-1A2 Gravitymaster watch, like new - jewelry - by owner - sale - craigslist