Being the first 100% sports watch by De Bethune, the GS Grand Blue features a new calibre. Entirely developed and manufactured by De Bethune, it is a hand-wound movement with central seconds and a five day power reserve, which is indicated on the dial. Water resistant to 100 meters, this watch offers excellent readability even in the darkest depths due to ingenious lighting inside the movement and a new photoluminescent blue. The rotating bezel is used to calculate immersion time, and generally