Fractional and Metric tap and die set. 5° Double Box Ratcheting Socketing arc with reversible lever eliminates hand over hand turning. Patented Twist Lock guide system reduces "back walk" of die guide. Ex tension adapters provide access in confined areas. Length of tap and die can be ex tended by Double Box Ratcheting Socketing Wrenchbining adapters and any 3/8" drive ex tension. Tap holders tilt down for easy access keeping taps secure and organized. Works with round and hex shaped dies. Includes sizes: 4-40 to 3/4" and 3mm to 18mm.