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Official Description

Use this app to practice opening a three number combination lock. Enter the three numbers for your lock combination. Then use your finger to turn the lock dial to open the lock. Trace along the outside of the lock. For the first number, turn the dial clockwise at least one full rotation to your number. For the second number, turn the dial counter clockwise at least one full rotation to your number. For the third number, turn the dial clockwise to that number.