Rolex is a company know for quality, luxury timepieces, and the Rolex Sea Dweller is no exception. The Rolex Sea Dweller, Rolex's deep sea diving model, has been one of the most popular Rolex models in the diving line, and is styled after the famous Submariner. While a jeweller is the true final authority on authenticity, some aspects of the watch can be checked by the user with a few simple tools.
Compare the price of the suspect watch. If the deal seems significantly better than other similar watches, be cautious. Most deals that seem too good to be true often are.
Check with the seller to see if the Sea Dweller includes the original box and papers. The papers will indicate the serial number, and the original place of purchase. Very few fakes will have a false set of papers, and they can be used to track a Rolex for authenticity.
Check the back of the case. Rolex Sea-Dweller casebacks will have "ROLEX OYSTER ORIGINAL GAS ESCAPE VALVE" engraved in an arc although some recent models may not have this feature. Any other design or engraving indicates that the Rolex is false.
Check the for a date magnification bubble. The real Sea Dweller does not have any bubble over the date, but many fakes will include the bubble as it is seen as a recognisable symbol of Rolex.
Unscrew the crown, and check for the Rolex Triplock seal. This is a rubber gasket under the crown on the stem of the crown that helps keep the water resistance of the watch. Most fakes will not include any sort of gasket under the crown.
Examine the face with a jeweller's loupe. Rolex is well known for creating well printed and immaculate watch faces, and any error or smudging may indicate a fake.
Bring the watch to a local Rolex dealer. The local dealer will be able to help determine if the watch is a fake.
No one test is 100%, and fakes are improving all the time. A Rolex jeweller is the only way to be certain.