1956 issue, based on the serial number 9085872

This watch has been in a drawer for at least 5 years and may require a proper cleaning, lube and calibration. I have no additional history of this watch except was one owner, my retired neighbor's, it winds and works. I had it running for three days with no issues and it kept good time.  

The quick release all leather strap appears very clean, new with no signs of wear 

Clean movement and crystal (review photos).   

Swiss Made 

The Vintage Longines 23ZS is an in-house high-quality, manual-wind mechanical movement introduced in 1948, known for its robustness, sweep seconds hand ("S"), and use throughout the 1950s. It features 17 jewels, a 19.8k bph oscillation, and often includes Super-shock-resist protection. It is a desirable caliber noted for being slim and reliable.