Will TAG Heuer’s carbon hairspring revolutionise watchmaking?

There’s change afoot in the watchmaking world, and TAG Heuer is leading the charge. At Geneva Watch Days 2025, the brand debuted a new hairspring (the spring in a watch attached to the balance wheel in the movement, which regulates time) made not of the traditional alloy or silicon, but instead, in carbon. The new moody-black forged-carbon hairsprings arrived in TAG Heuer’s two hallmark designs, the Carrera and the Monaco.

This is big news, as it is silicon that has gradually overtaken the 100-year-old Nivarox alloy as the material of choice for making the component that is the beating heart of a wristwatch, thanks to its stability over a range of temperatures and its imperviousness to the magnetic fields we constantly move through.

There’s a ‘but’, however, and that is silicon’s relative brittleness. It almost never happens, but silicon can crack under pressure and ‘almost never’ is too much for an industry that expects its products to work for decades. While makers such as Omega, Patek Philippe and Rolex have developed treatments that give silicon more strength, TAG Heuer has been working on an entirely new technology based on research into 'Carbon Infiltrated Carbon Nanotube-Templated Structures’.

The promise of carbon is a better security against environmental shocks, and grants more flexibility in designing the components, but along the way, there have been set-backs, cancellation threats, investment write-offs and more. Still, TAG Heuer promises that complementary technologies are in the pipeline and will feature in future collections.

Now, a decade since the project began, the TH-Carbonspring is in volume production with two limited editions being the first to utilise the new component: the Monaco Flyback Chronograph TH-Carbonspring and the Carrera Chronograph Tourbillon Extreme Sport TH-Carbonspring.

The details are suitably high-tech too, with the Monaco having black-gold-plated hour and minute hands filled with white Super-LumiNova, a black-gold small second hand and black forged-carbon indexes against a carbon dial. The Carrera has similar detailing but with lume-filled hour markers. Both are being produced in limited editions of 50. TAG Heuer says, with some justification, that this is the most fundamental development since the 17th century – and it might be right.

tagheuer.com