It was with OMEGA’s maritime legacy in mind that the brand launched its Planet Ocean line in 2005. The stylish OMEGA Seamaster Planet Ocean 600M Master Chronometer GMT pays homage to OMEGA’s dive watch heritage. This model, with its scratch-resistant sapphire crystal, features a black ceramic dial with Arabic numerals, a date window at the 3 o’clock position and a central GMT hand. Mounted on the 43.5mm stainless steel case is the world's first polished bi-ceramic black and white bezel. Here, the numerals and scaling are delivered in contrasting colors to separate night from day. Other features include an alveol screw-in caseback and a stainless steel bracelet with patented extendable foldover clasp. The OMEGA Seamaster Planet Ocean 600M Master Chronometer GMT is water resistant to 600meters and has a helium-escape valve. The OMEGA Master Chronometer caliber 8906 at the heart of this timepiece can be seen through the transparent caseback. To achieve Master Chronometer status, it has passed the 8 rigorous tests set by METAS (The Swiss Federal Institute of Metrology).<ul> <li>43.5mm stainless steel case</li><li>Black dial</li><li>600meter water resistance</li><li>Anti-magnetic</li><li>Chronometer</li><li>Date window</li><li>Helium escape valve</li><li>Screw-in crown</li><li>Bi-directional rotating bezel</li><li>Transparent caseback</li><li>Omega 8900 - self-winding movement</li><li>Domed, scratch-resistant sapphire crystal with anti-reflective treatment inside</li><li>Stainless steel bracelet</li><li>OMEGA Style#: O21530442201001</li></ul>