Oyster Perpetual is a term used by Rolex to describe a type of watch that features a waterproof case and a self-winding movement. “Oyster” refers to the waterproof case design introduced by Rolex in the 1920s and is still used in many of the brand’s watches today.

The Oyster case is made of a solid block of metal, which is tightly sealed to protect the watch’s movement from water, dust, and other external elements. The case features a screw-down crown and a screw-down case back, which provide additional protection against water and other elements.

“Perpetual” refers to the self-winding movement that powers the watch. The movement is powered by a rotor mounted on a central pivot, which winds the mainspring as it rotates with the movement of the wearer’s wrist. This self-winding movement is designed to be accurate and reliable and requires no manual winding or battery replacement.

Overall, the term “Oyster Perpetual” is used by Rolex to describe a watch that features a waterproof case and a self-winding movement and is a hallmark of the brand’s commitment to precision engineering, durability, and reliability.