ITEM NAME:3/8"-18 NPT Taper Pipe Tap High Speed Steel Metal Thread Cutting Tool 3 Gn.â— 1x Taper Pipe Tap. â— Spiral Tap the crumbs into a spiral up chip evacuation, it is more suitable for the. processing of blind holes and sticky materials processing. â— Spiral groove is conducive to remove crumbs, not easily broken tap.