This is the FIRST WATCH WORN ON THE MOON Steel Case Back which was made to commemorate the 1969 Moon Landing.
These are Omega supplied service case backs which fit the 42mm Manual Wind Moon Watch case reference 145.012. These service case backs have code st113901, this code 1139 is the old bezel code before 1589 which is why it is used on this case back.
This was fitted to the model stated above but will fit all the other case references for the 42mm Speedmaster Manual Wind Moon Watch models back to the mid 1960's once they introduced the crown guard Speedy.
112st113901 Omega Speedmaster 1969 FIRST WATCH WORN ON THE MOON Case Back
Items can only be returned if either faulty, in the case of the item not being required then it must be returned exactly as received. For example if the item is new in a sealed packet and/or has protective covers in place then it must be returned the same otherwise item is no longer new and the value is greatly reduced, these items can only be returned/refunded by agreeing a lower value with Swiss Limited Editions before returning reflecting the new lower value of the item.