KD Tools KDT-82812 114 pc - Large SAE-Metric Ratcheting Tap and Die Set Includes 4-40 to 0.75 and 3 to 18mm sizes 5 degree ratcheting arc with reversible lever eliminates hand over hand turning Patented Twist Lock guide system reduces back walk of die guide Extension adapters provide access in tight confined areas Length of tap and die system can be extended by combining adapters and any 0.375in drive extension Tap holders tilt down for easy access keeping taps secure and organized Works with round and hex shaped dies