- Professional helium velve on 9:00 o'clock, in order to be able to lead during external pressure reduction (e.g. emerging) the accumulating helium fast enough from the clock - central second indicator - Date indicator at 3:00 (quick winding with the crown on 4:00 at Pos. 1 clockwise rotation) - high quality automatic movement with 21 jewels - professional one side rotating bezel system - special coated luminous hands and digitsn "night employment suitably" - XL- casesize 52 mm; thickness 15,5 mm; all stainless steel - special "Polygon" screwed crown , diameter 5,5mm - WR 100bar "3280 feet" water resistant - SAPHIRE glas - screwed bottom "moderate temperature assembled" - high quality diver metall band with butterfly safty clasp Comment: The helium valve is especially for occupation diver interesting, who are held also in air environment on pressure. Helium atoms are so little that they can penetrate through sealings into the clock and can construct an interior pressure. This is further not tragically - if all helium atoms could leave in outside pressure reduction quickly enough the clock. For this case we add this special valve, which lets the helium-atoms again outward, otherwise it would come to an explosion of the clock!