Parlec S15-77TT5C Tapping Heads; Shank Type: Straight Shank; Shank Diameter (Inch): 1-1/2; Minimum Tap Capacity (mm): M3; Minimum Tap Capacity (Inch): #6; Maximum Aluminum Tap Capacity (mm): M39; Maximum Aluminum Tap Capacity (Inch): 1-5/8; Maximum M