Rolex Chronograph 4500

Reference 4500 is a very early Oyster Chronograph from the mid-1940s, often nicknamed the “Zerographe” or “Centregraphe.” It is technically significant as one of the first Rolex chronographs to feature a rotating bezel with a 60-minute/60-second scale, a precursor to later Submariner and GMT-Master bezels. It is a two-register chronograph, typically powered by the manual-wind Valjoux 22 movement. The 36mm Oyster case features pump pushers. The significance of the Ref. 4500 is its status as a pioneering tool watch, experimenting with external rotating bezels for elapsed time measurement.