Cal. 3131 is an anti-magnetic automatic movement produced by Rolex since 2007. It is based on the original Cal. 3130, dating back to 1988, and lacks modern advancements like Paraflex anti-shock, though it does have a Parachrom hairspring. It is likely that Rolex will replace this movement with the new “Chronergy” design in the coming years.
- 2016-present Rolex Air-King, Ref. 116900
- Rolex Milgauss, Ref. 116400