(TrendHunter.com) The G-SHOCK GRAVITYMASTER GR-B300 timepiece is being added to the brand’s range of watches to provide aircraft or aviation enthusiasts alike with the perfect option for their lifestyle. The…(TrendHunter.com) The G-SHOCK GRAVITYMASTER GR-B300 timepiece is being added to the brand’s range of watches to provide aircraft or aviation enthusiasts alike with the perfect option for their lifestyle. The…