5PCS NPT Pipe Thread Tap Set. Thread Standard: NPT. Round Shank with square end. Size: 1/8 "- 27 NPT, 1/4" - 18NPT, 3/8" - 18NPT, 1/2" - 14NPT, 3/4" - 14NPT. Thread Direction: Right. Right-hand cut tools have a cutting action that engages when they are run in a clockwise direction.
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