This Exceptional and extremely well-preserved Patek Philippe Ref. 3970EJ, a perpetual calendar chronograph in 18k yellow gold, offered in like-new condition. This iconic model features a 36mm case, crisp lugs, and both solid and sapphire crystal casebacks—a rare and complete configuration. The silver opaline dial is perfectly balanced, showcasing day, month, leap year, moonphase, and 24-hour indicators with elegant baton markers and leaf hands. Powered by the manual-winding caliber CH 27-70 Q, derived from the Lemania 2310 and heavily modified by Patek, this watch represents one of the finest traditional complications ever produced. Comes as an ultra full set: original box, papers, certificate, setting pin, and both casebacks. A true collector’s gem, combining vintage charm with investment-grade condition.