North American Tool 634107 Spiral Flute Tap, 1-12 UNF-3B (HS GH-4), is a spiral-flute internal-threading tap designed to cut 1-12 UNF threads. The spiral flute geometry aids chip evacuation during tapping, helping maintain alignment and reduce the risk of binding in the hole. Model 634107 denotes this tool for precision internal threading tasks with a 1-inch nominal diameter and 12 threads per inch in the UNF family.
