Shock-resistant watch

Common card · No. 423174

Shock resistant is a common mark stamped on the back of wrist watches to indicate how well a watch copes with mechanical shocks. In a mechanical watch, it indicates that the delicate pivots that hold the balance wheel are mounted in a spring suspension system intended to protect them from damage if the watch is dropped. One of the earliest and most widely used was the Incabloc system, invented in 1934. Before the widespread adoption of shock-resistant balance pivots in the 1950s, broken balance wheel staffs were a common cause of watch repairs.

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