The tool is a watch with an open and close screw-in back cover, which is convenient to use and easy to carry. (More practical, affordable, tool for unscrew watch)

(Open table diameter 3.70 cm, subject to bayonet) 3.7*3.5cm

This set of watch opener is equipped with 6 sets of steel teeth and a set of three. It can be replaced at will, and it can open most of the common screw-in watch back covers.