Crown guards are protective shapes on a watch case that stick out to shield the crown from knocks. They keep the crown from being damaged by an accidental blow. They matter most on sports watches and on watches that must stay water-tight.
What do crown guards look like?
Most crown guards are simple raised bumps on the case, next to the crown. On some watches the idea goes further, and the crown is set completely into the case body. Shapes vary. The Rolex Submariner reference 5512, for example, came with square-shaped guards. Whatever the shape, the job is the same: to keep the crown safe from accidental knocks. Crown guards are sometimes called shoulders.
Where it comes from
Panerai made the first crown protector in 1956. It was a bridge-type guard with a locking lever, developed for Italian navy divers. Rolex was the first brand to build the guards into the watch case itself. It introduced them on the Submariner in 1959 and patented the design. In the late 1950s, dive watches and other tool watches began to get crown guards. By the 1970s they were a normal feature on watches made to survive drops, dives or combat.
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