Case: An uncommon Longines stainless steel single button fly-back chronograph, 33mm diameter excluding the crown, curved bezel.
Dial: Matte silver dial, applied Arabic numerals, Feuille style hour and minute hands. Original gold minute recording hand and seconds hand.
Movement: Caliber 12.68Z
These single button chronographs — housing the 12.68Z — came in a variety of metals including gold plated, solid gold and stainless steel cases. There’s also a large range in sizes of case from the small 33mm (like the example shown here) to much larger 40mm stainless steel versions. The later are considered rarer and are considerably more valuable by collectors.