Achieve fast, precise National Pipe Taper (NPT) threads in through-hole work with the OSG NPT Spiral Point Threading Tap. Crafted from cobalt-enhanced HSS-E and finished with a Steam Oxide coating, it’s built for durability and consistent performance in demanding machining environments.

• Thread type: NPT spiral point threading tap designed for through-hole applications
• Size: 1/4" diameter, 18 TPI (1/4 x 18)
• Material: HSS‑E (high-speed steel with cobalt) for enhanced hardness and heat resistance
• Coating: Steam Oxide coating to improve wear resistance and lubrication
• Geometry: Spiral flute with a spiral point to promote immediate chip evacuation
• Application: Ideal for through-hole NPT tapping in production and repair work

The spiral point design ensures chips are pushed ahead of the tap, reducing recutting and improving cycle times on through holes. The HSS‑E core maintains sharpness under elevated cutting temperatures, while the Steam Oxide coating adds a protective layer to extend tool life and resist corrosion. This combination delivers clean, accurate threads that seal reliably in piping connections, supporting repeatable results across multiple parts and setups.