Military Ronda Quartz GTLS Watch. These watches were ordered by submarine crews specifically for this purpose. Luminosity: GTLS T100 Tritium on Hands & Dial. All MWC 500 m (1,650ft) models are fitted with a helium escape valve, people often ask us how helium gets into a dive watch in the first place and the answer is amazingly simple, essentially a helium molecule is among the smallest of all molecules.
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