Levmaster Sub Professional 300 Helium Valve men's watch, Levrette underwater model equipped with the automatic helium gas expulsion valve. This feature much appreciated by professional divers allows you to reach a depth of 300 meters without problems.
The bezel is unidirectional with 60-120 clicks and as befits a professional unidirectional counterclockwise instrument, this is to avoid that a random and involuntary movement of the numbered bezel can lengthen the limit times beyond the expected time to recover decompression times during the ascent to the surface.
The glass is obviously in scratch-resistant sapphire and treated with anti-reflection on the inner side, this is to avoid that a line on the surface during sports use cannot be repaired except by replacing the glass.
To facilitate the reading of the date at 3 o'clock, the glass also features a magnifying glass.
The movement is automatic, ETA 2789. The unidirectional bezel is in ceramic. The crown, characterized by a functional knurling to facilitate grip and operation. The winding crown is screwed to the case and guarantees water resistance thanks to the gasket (1-2) as regards the helium expulsion valve, this will be activated automatically during the emergence from the dives. The steel bracelet is equipped with a comfortable and functional professional buckle that provides an additional stretch mesh to be able to wear it over the neoprene wetsuit.

- Material: Steel
- Diameter: 43 mm
- Glass: Sapphire
- ATM system: 30
- Crown: Screwed
- Case Back: Screwed
- Movement: Auto ETA 2789
- Bracelet and Size: Steel bracelet 22x18
- Buckle: Deployant and Logo
- Dial: Superluminova indices