Here is an attractive Omega Seamaster Automatic Calendar watch. This automatic calendar watch is the third generation of the "Seamaster Calendar" model, and it is the first Omega Seamaster model to carry a calendar disc for the 3 o'clock position. The 20 jewels movement is an Omega caliber 503 with a swan neck regulator. It has been fully serviced and running accurately. The movement serial number is 16962646, dating this watch to 1958. Uncommon luminousless original dial in well-aged condition. Original signed crown. Crystal is brand new—brand new 18mm matching high-quality genuine leather strap. The solid stainless steel original case measures 34.4mm, excluding the crown by 41.5mm lug tip to lug tip. Case model 2849-1 SC. The calendar feature is working accurately. The wrist size in the photo is 6 inches.