Best Npt Tap Drill Size Chart

• Thread Size: 1/4-18 NPS
• Thread Length: 30mm / 1.18 inch
• Shank Side Width: 8.8mm / 0.35 inch
• Material: HSS (High Speed Steel)
• Total Length: 94mm / 3.7 inch
• Straight 4 flutes are ground to provide rapid chip removal for efficient threading.

• Heat treated and tempered for file hard threads, and longer, useful life
• Designed for hand cutting applications
• National pipe thread
• Very strong and durable
• Easy to use

• Thread Size: 3/8-16 BSW
• Shank Side Width: 6mm / 0.24 inch
• Thread Length: 25mm / 1 inch
• Material: HSS (High Speed Steel)
• Total Length: 74mm / 2.9 inch
• Straight 3 flutes are ground to provide rapid chip removal for efficient threading.

• Each size has a nut and bolt checker on the same gauge. 26 male/female gauges - 14 inch & 12 metric.
• Thread sizes are permanently stamped onto each gauge (inch in red, metric in white)
• Inch gauges are clear zinc plated, metric gauges are black oxide.
• The individual gauges rotate freely on the wire cable for fast thread verification
• Wire cable with loop for convenient hanging