Features and Benefits:Restores and cleans up threads on nuts, bolts, and studsInternal thread restore range 1/2î to 3/4î (M12 to M20)External thread restore range 1/4î to 3/4î (M6 to M18)Tools automatically adjust to thread diameter and pitchCan be used on both right and left hand threads, both inch and metric as well as coarse and fine thread ....(more info)