Rolex produced only two different models of wristwatches with moon phase, the references 8171 and 6062. Both models are automatic, however references 8171 feature a snap-on case back, while the reference 6062 features a water-resistant-type screw back. Reference 8171 was made in a small series between 1949 and 1952, mostly in yellow gold. Examples in pink gold and stainless steel are very rare.
Reference 8171 is popular amongst collectors, thanks to its large diameter and dial design.