An expert diver’s watch is another essential timepeice every serious watch collector should consider having in their collection. A locking screw-down crown and case back with water-resistance to 200 meters or more is perhaps the most essential elements to consider when purchasing a  true diver’s watch, since it is necessary to protect the interior movement of a fine timepiece whether you’re scaling the ocean’s floor or swimming laps in the pool. A unidirectional rotating bezel is another aspect to consider to keep track of dive times while you’re under water. The watch material is another factor to take into consideration. Both stainless…