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Watch winding and time-setting mechanism that operates without a separate key, using a crown-operated system introduced in the mid-19th century.

Keyless works is the mechanism that allows winding and time-setting without a separate key (used in antique watches). Invented by Adrien Philippe in 1844, it uses a winding stem with multiple positions: pushed in for winding, pulled out for setting time, and sometimes intermediate positions for date/complications.
The system uses a sliding pinion on the winding stem that engages different gear trains depending on crown position. When pushed in, it connects to the winding mechanism. When pulled out, a clutch disengages winding and engages the setting wheels to move the hands. The keyless mechanism revolutionized pocket watch convenience.
Yes, keyless works components (clutch wheel, setting lever, detent springs) can wear or break from improper handling. Forcing the crown, pulling too hard, or winding while in setting position can damage the mechanism. Quality watches have robust keyless works, but gentle operation extends longevity. Repair requires watchmaker expertise.

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