High Speed Steel Straight Flute N.P.T. Taper Pipe Reamers are multi-fluted, end cutting tools used to resize and clean up previously formed holes prior to tapping. Taper is 3/4" per foot. Taper Pipe Reamers have a left-hand spiral and right-hand cut, and are driven by a straight or T-handle tap wrench attached to the square drive area of the shank. The cutting end is ground with a 45° chamfer angle for easy entry into the hole. Suitable cutting oils or appropriate coolant fluids are recommended for most reaming operations.