Features The taps and dies in these sets are made from carbon steel. They are an economical choice for internal- and external-threading applications in maintenance operations. Number of Pieces / 24 Number Of Taps / 11 Number of Dies in Set / 11 Tap Type / Straight Flute Thread Standard / NC, NF, NPT Thread Sizes Included / 1/2"-13, 1/2"-20, 1/4"-20, 1/4"-28, 1/8"-27, 3/8"-16, 3/8"-24, 5/16"-18, 5/16"-24, 7/16"-14, 7/16"-20 Threads per Inch / 13, 14, 16, 18, 20, 24, 27, 28 Tap Series / Hanson Class of Fit / 2B Drill Bit Size / #3, #7, 25/64 in, 27/64 in, 29/64 in, 5/16 in, F, I, Q, U Helix Angle / 0 Degrees Number of Flutes / 3, 4 Die Material / High Speed Steel Die Shape / Hex Die Type / Solid Die Thread Sizes Included / 1/2"-13 NC, 1/2"-20 NF, 1/4"-20 NC, 1/4"-28 NF, 1/8"-27 NPT, 3/8"-16 NC, 3/8"-24 NF, 5/16"-18 NC, 5/16"-24 NF, 7/16"-14 NC, 7/16"-20 NF Die Hex Size / 1 in 55% Thread Drill Size / # 3, 10.20mm, 11.30mm, 11.80mm, 11/32 in, 5.70mm, 8.40mm, 9/32 in, I, W 65% Thread Drill Size / # 5, 10mm, 11.60mm, 11mm, 17/64 in, 7/32 in, J, P, R, V 75% Thread Drill Size / # 7, 11.40mm, 27/64 in, 5.45mm, 5/16 in, 8.50mm, 9.95mm, F, I, U Die Material Grade / Carbon Steel Material - Machining / High Speed Steel Max. Die Thread Size / 1/2"-20 Max. Tap Thread Size / 1/2"-20 Measurement System / Fractional Inch Min. Bore Dia. / 1/8 in -27 NPT Min. Tap Thread Size / 1/8"-27 Spiral Direction / Neutral Tap Sizes Included / 1/2 in -13 NC, 1/2 in -20 NF, 1/4 in -20 NC, 1/4 in -28 NF, 1/8 in -27 NPT, 3/8 in -16 NC, 3/8 in -24 NF, 5/16 in -18 NC, 5/16 in -24 NF, 7/16 in -14 NC, 7/16 in -20 NF Tap Chamfer / Plug Tap Material / High Speed Steel Tap Wrench Number / 12421 Thread Direction / Right Hand Thread Type / NC, NF, NPT