Rolex

I bought this vintage Rolex most of a year ago..was wondering is anyone knew more about it...all I know is it's from the 60's.....and the dealer had an original Rolex magazine ad with this model pictured and it was referred to as "Tank"...  

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Manual wind Rolex OysterDate Precision watch with a re-painted "bow-tie" dial, and in nicely restored condition. The Tank watch is generally a non-Oyster, rectangular shaped manually wound watch, originally attributed to Cartier, and based on the shape of...