Reference 1463 was launched in 1940, and remained in production until approximately 1965. It was Patek Philippe first and only vintage waterproof chronograph, thanks to its screw back case and round pump pushers (for which it was nicknamed "Tasti Tondi" by Italian collectors). Reference 1463 was a sportier alternative to the classy chronograph 130, and it was designed for a contemporary society with an increasing interest in outdoor activities. To the best of our knowledge, 750 specimens were produced in total, with the majority in yellow gold, and a very limited number in rose gold or stainless steel.Remark: According to Patek Philippe archives, the case of the present watch was changed during a servicing in their workshops in 1987, with the new case back mistakenly engraved 1363 instead of 1463.