YG-1 Straight Flute Hand Tap, Oversized Square Shank, Series: T7326, Measurement System: Imperial, UNC Thread Standard, 1/4-20 Thread, Plug Chamfer, 4 Flutes, HSS, Uncoated, 1 in Thread Length, 2-1/2 in Overall Length, 0.255 in Shank Diameter, Low Carbon Steels, Free Machining Carbon Steel, Medium to High Carbon Steels, Low Alloyed Steels, Free Machining Stainless Steels, Pure Aluminum, Aluminum Alloys, Aluminum Alloy Castings, Pure and Alloyed Copper, Free Machining Brass, Alloyed Brass, Zinc and Magnesium Material Application, 0.005 in Thread Limit, Yes Through Coolant