OSG Threading Tap - UNC Spiral Point HSS-E - Steam Oxide Coated - Through Hole - No. 4 x 40

The OSG UNC Spiral Point Threading Tap is designed for machinists who demand clean, precise through-hole threads with impressive tool life. Built with HSS-E cobalt and a durable Steam Oxide coating, this tap combines toughness, heat resistance, and smooth cutting performance for everyday tapping tasks.

• No. 4 x 40 UNC: Spiral point threading tap optimized for through-hole applications and standard 4-40 threads.
• Material: HSS‑E (high‑speed steel with cobalt) for greater hardness and wear resistance in demanding metals.
• Coating: Steam oxide coating reduces friction and enhances durability in cutting conditions.
• Geometry: Spiral point design facilitates efficient chip evacuation and straight, accurate thread formation in through-holes.
• Application: Specifically engineered for through-hole tapping, delivering consistent thread quality and extended tool life.
• Brand & Technology: OSG’s advanced threading technology supports precise, reliable results across production runs.

This tap helps you achieve repeatable, high-quality No. 4-40 threads with reduced downtime thanks to effective chip control. The HSS‑E cobalt composition withstands higher cutting temperatures, enabling smoother feeds and longer life in tougher materials, while the steam oxide coating adds durability and better lubrication in operation. The spiral point geometry speeds up tapping and minimizes the risk of thread distortion, making it a dependable choice for through-hole assemblies in automotive, electronics, and general machining environments. For best results, maintain proper lubrication, use the correct drill size for your material, and follow standard tapping practices to maximize tool life and thread integrity.