Patek Philippe – Ref. 3970, perpetual calendar chronograph, white gold, with Patek extract of archives Model: Perpetual Calendar Chronograph Material: White gold Reference N°: 3970 E Year: Circa 2003/2004 Case N°: 4197756 Caliber: CH 27702 Bracelet: Leather strap with white-gold buckle Dimensions: 36.5 mm Signed: Dial, case, movement and strap Accessories: Patek Philippe extract of archive The perpetual calendar chronograph wristwatch, reference 3970, was released from 1986 to 2006. It was cased in platinum, white gold, pink gold and yellow gold. There are three series in which reference 3970 was produced: the first series featured a snap back case. The second series featured a solid case back, and was produced concurrently with reference 3971 with a snap sapphire case back. The third series, like this example, was accompanied with “E” for “étanche” or waterproof. 3970 Was the first reference to use a lemania 2310 based movement, not a Valjoux movement. The present watch is in good overall condition, with a crisp hallmark under the lugs and a Patek Philippe extract of archives newly issued. Montre en or gris, « Chronographe Calendrier Perpetuel », réf. 3970. Accompagnée d’un extrait d’archive Patek Philippe du mois de novembre 2018. Très bel état.