The Speedmaster was the first watch to feature a tachymeter
link on the bezel as opposed to being incorporated into the dial. This opened up the dial
link allowing for
link a better visual balance between the indices which are fashioned from white gold on the Racing Master Chronometer and the seconds track but it also gave the tachymeter more room to breathe. Decoupling the tachymeter from the rest of the bezel ultimately made the watch more legible and in turn easier to use.