First launched in 1936, the Longines 13ZN chronograph movement is still considered today as one of the most beautiful and technically interesting wristwatch chronograph movements ever produced. Designed as a flyback chronograph, where a user can quickly reset the chronograph seconds hand to zero while it’s running, almost all 13ZN-based chronograph wristwatches sold incorporated this convenient function.

Hardly ever seen, the reference 5415 is a rare snap-down caseback model, rather than the more well-known “Tre Tacche” models with screwdown cases. A double flap on the caseback aids opening and servicing. The black luminous dial is entirely original and beautifully preserved, reacting correctly under UV light. The batch number of 28 engraved on the caseback matches the same number underneath the lug. Interestingly, the movement is stamped ‘13NZ’ in what has been confirmed by the manufacture's Heritage department as a rare factory error. Preserved in excellent overall condition, it’s a wonderful example for the collector, originally sold to Longines' agent in Sweden.