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  The anti-theft shut-off valve is a valve product that has been successfully designed to solve the problems of delayed payment by users in heating systems and losses caused by frequent island oil incidents in oil fields. This anti-theft shut-off valve has good anti-theft performance (three insurances), easy opening and closing, stable sealing effect, and long service life.
  Instructions for using anti-theft shut-off valve: After installing the anti-theft shut-off valve, use the small hexagonal screw on the upper end of the accessory wrench to unscrew the small internal hexagonal screw on the valve cover, remove the cover, and the middle is the lock cylinder. If you have a key lock cylinder, use the key to open it. If you have a password lock cylinder (see password coding and use for anti-theft valves), take out the lock cylinder, and use the lower end of the accessory wrench to open (or close) the butterfly plate of the valve. Close it clockwise and counterclockwise.