Watch will be pre-test...Watch will be re-sealed to ensure the watch withstand pressue testing of 5 atm.. 50 meters... Methods of Testing : Dry Pressure Chamber Method..  

All HE valves are a source of leak.. It will be lock dead in order for the watch to maintains its waterproofing capabilities..

Before checking this item for purchase.. please email us to ensure that the watch in question can be waterproofed.... especially chronograph watches.. some watches are contructed in a way that it cannot be pressure tested.. E.g. Breitling Navitimers