- Brand: Rolex
- Circa: 1940
- Model: Oyster Perpetual
- Reference: 3131
- Calibre: 9 3/4'''
- Movement: Automatic
- Material: 14ct rose gold
- Features/complications: Bubble back
- Dial: Black dial with outer minute track featuring luminous baton hour indices and Arabic quarters with luminous Oyster hour and minute hands and sweep centre centre seconds
- Case dimensions: 32mm
- Bracelet/strap: Leather strap
- Accessories: N/A
- SKU: 2236
Essay: Rolex created the auto-rotor movement from the Aegler movement in Hunter watches that featured a “perpetual motion” winding mass. Rolex subsequently patented its first successful perpetually self-winding wristwatch in 1932 and the Bubble Back was introduced in 1933 and featured the first auto-rotor. The reference 3131 is yet another model of a long line of a Oyster Perpetual wristwatches since their inception in 1926