Inspired by the waterproof timepieces of military standard, the Omega Seamaster surprised upon it’s debut with a unique O-ring gasket that served to actively enhance the watch’s water-resistant qualities. Before this, water-resistant products used either shellac gaskets or lead items, that could be rendered useless by the extreme temperature shifts that frequently occur under the water. The hardy rubber gasket on the Omega Seamaster ensured that this would not be an issue and that the case would stay perfectly in order at depths of up to 60 metres and temperatures approaching as little as -40 degrees.