Case diameter is 38 mm. Sporty and elegant Stainless Steel watch with 10 bar water resistance and date indication. The watch comes with a trendy interchangeable nato strap. OXYGEN PARIS Inspired by the sports fashion trend, Oxygen's new signature Exchange collection was launched in July 2011 in France and is now available in more than 20 countries. The trendy watch brand with interchangeable NATO straps is following the emerging trend of personalisation and interchangeability. The "Sport" and "Diver" models come with 1 interchangeable nylon strap, like those used by NATO soldiers. These straps can be easily switched in a matter of seconds, no tools required. The straps are very strong, dry instantly and allow you to match your watch to your outfits and your activities. Sold separately, Exchange straps come in a wide range of plain and striped colours. The entire collection is made of Stainless Steel cases and is waterproof to 100M/10ATM.