Part of the Patek Philippe 175th anniversary limited edition commemorative series, the reference 5975 is the first self-winding chronograph-only wristwatch ever produced by the manufacture. It is also the firm's first chronograph without registers or subsidiary seconds and differs from previous Patek Philippe wristwatches through its multi-scale dial. Featuring a telemeter scale to compute distances, tachymeter scale for speed and pulsation scale for heart beats, the reference 5975 is the first Patek Philippe chronograph to enable all these measurements. Following firmly in the tradition of Patek Philippe's best mid-century vintage chronographs, the dial of the 5975 is a masterful piece of design, managing to remain understated and elegant despite its complexity