Offered here is a rare Longines chronograph, circa 1960-1970s, powered by their Cal. 13ZN predecessor – the 30CH. This example, the Reference 7413, is fitted in a large, steel case, and features a screwback waterproof layout, and pump pusher chronograph buttons. This Longines chronograph is in excellent vintage condition. The case is unpolished and sharp, with original bevels in the lugs. The sunburst dial is in great condition, with no major wear/flaws.