Abstract: A crown tightening tool is constituted by an engaging part which can be engaged with a crown projected form a watch body of a wristwatch, and a handle part which is engaged with the engaging part and rotates the engaging part. The engaging part is formed by grooves to engage and rotate the crown. The crown tightening tool can be worn by a user as an accessory.
Abstract: The crown tightening tool can be carried as an accessory by a user of a wristwatch and the user can always perform the tightening of the crown.