Seiko & Citizen Watch Forum Message Archive

Being He-resistant. Yes the L-shaped gasket is special in it, having a larger surface, giving it a better constant factor in keeping Helium outside the watch, but believe me, Helium will enyter the watch.

The factor which is the best for Helium resistant (on the old Seikos) is th ecrystal retainer ring, this prevents the crystal from popping of the watch, in case the innner pressure is higher than the outher pressure. On newer watches thecrystal simply is pressure fitted with a hard plastic (mostly white) ring. If the pressure difference exceeds say 1.5 to 3 bar, the crystalwill simply pop of the watch.

Some Tuna's and the Auto-zilla en ECO-zilla have screwed down crystals, thus a lage 'nut' screws down the crystal, keeping it in place if inside pressure is greater than outside pressure.

some watches do however feature a He-valve, simply stating the watch is proffesional and it functions much more quicker.

Bart