Unique Bargains High Speed Steel 17mm Thread Dia Straight Machine Plug Tap Z3/8-18

High speed steel, 4 flutes, 60 degree thread.
Suitable for machine use to cut threads to the bottom of a blind hole.
A bottoming tap ( plug tap ) is usually used to cut threads in a hole that has already been partially threaded using one of the more tapered types of tap.
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