TapMatic RX70 Tapping Head (2) Model RX70, Shank Type: Taper, Taper Size: JT3, Minimum Tap Capacity (Inch): #10, Minimum Tap Capacity (mm): M5, Maximum Aluminum Tap Capacity (mm): M18, Maximum Aluminum Tap Capacity (Inch): 3/4-16, Maximum Mild Steel Tap Capacity (mm) :M18, Maximum Mild Steel Tap Capacity (Inch): 3/4-16, Gear Ratio: 1.75:1, Maximum RPM: 1200, Body Diameter (mm): 88.00, Overall Length (mm) 182.00