Vintage Zenith "El Primero" Rainbow Flyback Reference 01.0480.405 circa 1999 Movement: The Swiss-made "El Primero" self-winding chronograph movement, a proven and robust engine, still in use by Zenith today, also powered early Rolex Daytona references. In this watch, the variant is an El Primero caliber 405, with a "retour en vol" or "flyback" complication. The flyback feature is used primarily in aviation navigation applications to quickly reset the sweep seconds hand "on the fly" without first stopping it. Quickset date display at four-thirty. All functions are working properly and keeping excellent time. Case & crystal: 40mm brushed stainless steel with screw-down back, bi-directional bezel, and sapphire crystal. Included are both an aftermarket Thomas Priek display case (currently installed) and the original OEM case which still retains a bit of the purplish "goo" that Zenith used to protect new watches from scratches prior to sale. It has obviously been worn sparingly over its life - the case is unpolished and has only minor imperfections from use that are difficult to see without close inspection. Dial, bezel, and hands: Chronograph dial with minutes, hours, and running seconds sub-registers. Dial and bezel are exceptional, even under close inspection, with bright and vivid colors. The hour, minute, chronograph sweep, and sub-register hands are all correct. Strap and Bracelet: When sold new, this reference was fitted with a sharkskin strap and deployant clasp - the originals are included. Purchased separately, and currently installed on the watch, is a period-correct Zenith OEM bracelet. This version, also included, was fitted to the 02.0480.405 version of this watch - the only difference between the two references and therefore perfectly matched to the case. Box: The correct box is included - it came with the watch when purchased - there are no papers. The coating on the cushion is visibly flaking. The box and inner lining are otherwise in very good condition, with some imperfections from age. Overall, a top-condition example of a classic Zenith El Primero reference. $5500 OBRO, shipping included by FedEx 2-day in the USA. Payment via bank wire only. No returns. Please be an informed buyer, do your own research. Happy to answer any questions you may have.