For the Only Watch 2013 charity auction, Patek Philippe has produced a one-of-a-kind version of the discontinued ref. 5004 in titanium called the 5004T.

The Patek Philippe Ref 5004 is a split-seconds chronograph + perpetual calendar; it was produced for about six years, until being replaced by the Patek Ref 5204 in 2011.

Not only is it the fourth Patek in titanium, ever to be made, it is also a ref. 5004 that is not in the current collection anymore, so it might be considered a last chance for collectors to buy this desirable timepiece.

Aside from the chrono and perpetual calendar displays, the dial on the watch is quite interesting — made of solid gold, it is engraved to look like carbon-fiber. Similarly is the strap, actually made of calf skin, it is embossd to resemble carbon fiber.

The watch is powered by the Patek Caliber CHR 27-70 Q which is based on the Lemania 2310 caliber.

The biennial.“Only Watch” charity watch auction, to be held in Monaco on September 28, will donate all its .proceeds to research for Duchenne muscular dystrophy.