he split-seconds chronograph is one of the three most difficult complications to master, alongside the tourbillon and the minute repeater. It takes a highly sophisticated mechanism to control the two chronograph hands, one of which may be stopped to measure an intermediate or lap time or retain a reference time while the other continues its course unaffected, even by
fractions of a second. When released again, the split-seconds hand instantly catches up with the primary hand and the two stacked hands move on together.

Manually wound mechanical movement. Caliber CHR 29-535 PS. Split-Seconds chronograph. Instantaneous 30-minute counter. Seconds subdial. Tachymeter scale. Dial: authentic black enamel, gold applied Breguet numerals. 18K gold dial plates. Alligator strap with square scales, hand-stitched, shiny black, fold-over clasp. Case: platinum. Interchangeable full back and sapphire-crystal case back. Water resistant to 30 m. Case diameter: 41 mm. Height: 13.56 mm.

Within the broad repertoire of complications that Patek Philippe masters so consummately, the split-seconds chronograph occupies an important position. Its ingenious function allows lap and intermediate times to be stopped without interrupting an ongoing measurement. The first Patek Philippe chronograph for the wrist, launched in 1923, already had the rattrapante feature. As a successor to this exceptional line, the Ref. 5370 grand complication wristwatch sports a newly developed split-seconds mechanism with technical-masculine charisma, crowned by a black dial in genuine enamel.