Here is a rare Omega Seamaster Automatic Calendar watch. This one was made for the US market (OXG on the balance bridge indicates that), and some of the US market version of this reference will come with a plain dial without the words "Seamaster Calendar" on the dial. This bumper automatic calendar watch is the first generation of the "Seamaster Calendar" model, and it is the first Omega watch movement to carry a calendar disc. The 17 jewels movement is an Omega caliber 353 with a pointer regulator. It has been fully serviced and running accurately. The movement serial number is 12527234 dating this watch to 1952. Waffle texture original dial in well-patina condition. Gold original set of dauphine hands. Original signed crown. Crystal is brand new. Brand new 18mm matching high-quality genuine leather strap. The gold-capped over steel original case measures 35.3mm excluding the crown by 43.4mm lug tip to lug tip. Case model 2627 - 2 SC. Calendar feature working accurately. This watch is in its original unpolished condition. The wrist size in the photo is 6 inches.