Fun Fact: James Bond wore the Seamaster 300M in Tomorrow Never Dies, The World is Not Enough, and Die Another Day. The Seamaster 300 is equipped with a helium escape valve, which is one of the watch’s main selling features. In newer models, the valve is artfully crafted as a conical shape and patented by technology, rendering it water-resistant for 50m even if accidentally left open. The back of the watch features a sapphire crystal and wave-patterned edge on the caseback. When priced at $2260-$2441, the Seamaster 300 tends to sell in 3.9 days, which is pretty interesting considering the fair market range is $1,662 - $2,178.