Patek Philippe

Launched in 1986, the reference 3970 was Patek Philippe’s third perpetual calendar chronograph made in series. Powered by the Lemania 2310 as its base, the caliber CH 27-70Q was heavily modified by Patek Philippe. The reference 3970 was the first perpetual calendar chronograph made by the firm to indicate the leap years.

The first series of the 3970 featured a solid snap-on case back. It was later replaced with Ref. 3970E like the current example, which features an updated screw-down case back, with the suffix indicating étanche, or waterproof. This screw back case back was produced for the second to fourth series of the model until the Reference 3970 ceased production 2004.

The reference was a complete success and was kept it in production for almost twenty years, making it in yellow, pink and white gold, and in platinum. The present example is in close to new condition with terrific and well-defined fluting to the lugs, a sought-after two-tone 24-hour register, and is complete with its certificate of origin, box and additional solid second case back.