Wittnauer chronograph vintage

Mens Wittnauer 2 Register Chronograph, Caliber Y 14, Swiss, with movement made by Landeron caliber 129 for Wittnauer. Watch is stainless steel, probably 50's. Inside back reads3256 and back reads6440660. Watchis running and gains about two minutes a day. The chronograph functions correctly start stop and back. The one chrono is missing the button but the stem and module are there and the chronograph works. The watch measures 35 mm across the front and watch is equipped with new acrylic crystal.