New steel crown tube for Audemars Piguet Royal Oak Offshore 25940 and 26170.

1. You need the TUBE, otherwise the Audemars Piguet Crowns can not fit on the AP model.  The screws usually get worn up on the old AP crown, and you will need a new TUBE to correctly plug the new crown.
2. Please consult with your watchmaker on the correct tube and crown, as sometimes watchmakers don't know that and try to plug in the new crown into an old, damaged thread, and it will not fit.

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