It was with OMEGAs maritime legacy in mind that the brand launched its Planet Ocean line in 2005. Today, the stylish OMEGA Seamaster Planet Ocean 600M Master Chronometer pays homage to OMEGAs dive watch heritage. This model, with its scratch-resistant sapphire crystal, features a blue ceramic dial with Arabic numerals and a date window at the 3 oclock position. The blue ceramic unidirectional bezel with OMEGA Ceragolddiving scale is mounted on a 43. 5 mm 18K Sednagold case. Other features include an alveol screw-in caseback and a blue leather strap with rubber lining and an 18K Sednagold clasp. The OMEGA Seamaster Planet Ocean 600M Master Chronometer is water resistant to 600 metres / 2000 feet / 60 bar, and has a helium-escape valve. The OMEGA Master Chronometer calibre 8901 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