El Primero A3817

An original El Primero combining an angular steel tonneau case with a white tricolour chronographChronographA watch function for starting, stopping and resetting an elapsed-time measurement independently of the ordinary time display. dial. Blue running-seconds markings and hand, a grey tachymeterTachymeterA chronograph scale that converts the time taken to travel a known distance into average speed. The distance and scale units must correspond./pulsometerPulsometerA chronograph scale estimating heartbeats per minute from the time taken to count the number of beats specified on the dial. ring and a pointed fractional-seconds track distinguish it from the round-case A386.