Dial: black Calibre: cal. 4030 automatic, 31 jewels Movement number: 158’098 Case: stainless steel Oyster, screw-down crown and back Case number: U’644’870 Closure: stainless steel Rolex Oyster bracelet with integrated folding clasp Dimensions: 40mm diameter, bracelet circumference approximately 175mm Signed: case, dial and movement Accessories: Rolex guarantee, original invoice dated January 24, 1999, Rolex Oyster, Cosmograph and service booklets, presentation case with outer packaging

DIAL: in very good condition. Hands also in very good condition CASE: with light scuffs and marks throughout, but still retains good definition. indentation to the edge of the upper right lug. Small dent to the inner edge of the bottom left lug Bracelet: ref. 78390 (U6) / 78390, 503B endlinks. With heavy scuffs throughout MOVEMENT: running at time of cataloguing, chronograph starts, stops and resets to zero Please note that the movement has not been tested for the accuracy of its timekeeping. Please note that Sotheby's does not guarantee the future working of the movement and that a service may be required at the buyer's discretion.
"In response to your inquiry, we are pleased to provide you with a general report of the condition of the property described above. All dimensions in catalogue descriptions are approximate. Condition reports may not specify mechanical replacements or imperfections to the movement, case, dial, pendulum, separate base(s) or dome. Watches in water-resistant cases have been opened to examine movements but no warranties are made that the watches are currently water-resistant. Please note that we do not guarantee the authenticity of any individual component parts, such as wheels, hands, crowns, crystals, screws, bracelets and leather bands, since subsequent repairs and restoration work may have resulted in the replacement of original parts. Since we are not professional conservators or restorers, we urge you to consult with a restorer or conservator of your choice who will be better able to provide a detailed, professional report. Prospective buyers should inspect each lot to satisfy themselves as to condition and must understand that any statement made by Sotheby's is merely a subjective, qualified opinion. Prospective buyers should also refer to any Important Notices regarding this sale, which are printed in the Sale Catalogue. In particular, please note it is the purchaser's responsibility to comply with any applicable import and export matters, particularly in relation to lots incorporating materials from endangered species.NOTWITHSTANDING THIS REPORT OR ANY DISCUSSIONS CONCERNING A LOT, ALL LOTS ARE OFFERED AND SOLD AS IS" IN ACCORDANCE WITH THE CONDITIONS OF BUSINESS PRINTED IN THE SALE CATALOGUE."

**Please be advised that bands made of materials derived from endangered or otherwise protected species (i.e. alligator and crocodile) are not sold with the watches and are for display purposes only. We reserve the right to remove these bands prior to shipping."

The reference 16520 was revolutionary in the history of the Daytona.
After 25 years of manual winding chronographs housed in a similar case design (with the exception of the screw-down pushers), Rolex introduced the new model powered by the Zenith El Primero-based automatic calibre 4030 and had a totally new, more modern and robust case design. 
Over the 12 years of its lifetime, the Zenith Daytona underwent a few changes including five versions or 'marks' of the dial, the last one being the introduction of the luminova in 1998, and new bracelet design. 
This particular lot is a U series from 1997. It has the correct Mark 4 dial which was the last one produced with tritium as luminescent material.
Presented on behalf of an important private collector, the watch impresses by retaining its strong proportions and having a most attractive black dial confirmed by the guarantee, its original 78390 bracelet with 503B end links as well as all its accessories. 
It represents an excellent opportunity to acquire an increasingly sought-after model.