PATEK PHILIPPE. A VERY FINE AND RARE PLATINUM PERPETUAL CALENDAR SPLIT SECONDS CHRONOGRAPH WRISTWATCH WITH MOON PHASES, 24 HOUR AND LEAP YEAR INDICATION

Reference 5004 is considered a modern classic and derives its features from reference 3970, which itself is based on the legendary reference 2499. However, reference 5004 steps up a gear in terms of complication by boasting the highly complex split seconds function. Reference 5004 is roughly one millimeter larger than reference 3970 and also easily recognizable by its oversized split-seconds pusher in the crown. Production of reference 5004 began in 1994 and is today discontinued. Patek Philippe replaced it with two other split seconds chronograph models, both in platinum cases: the cushion-shaped reference 5951 released in 2010 with in-house calibre CHR 27-525 PS Q and reference 5204, released in March 2012 at the Basel Fair with in-house calibre CHR 29-535 PS Q.