Drill America DWT Series Qualtech High-Speed Steel Round Adjustable Pipe Threading Die, 1-1/2" Diameter, 1/4" NPT (Pack of 1) High-speed steel tools are good for most general purpose applications, offering a combination of hardness and toughness for wear resistance Round die is chamfered on both faces Adjustment is obtained by a fine pitch screw which forces the sides of the die apart, or allows them to spring together