Jaeger-LeCoultre is a Swiss manufacture founded in 1833 by Antoine LeCoultre in Le Sentier in the Vallee de Joux, owned by Richemont. It has developed more than 1,200 calibres and historically supplied movements to Patek Philippe, Vacheron Constantin and Audemars Piguet, which is why it is called the watchmaker's watchmaker. Its signature model is the Reverso, created in 1931 with a case that swivels to protect the crystal during polo, alongside the Master Control, Duometre, Polaris, Rendez-Vous and the Atmos clock that runs on temperature change alone.