20 Piece BSF Tap Die Set 3/16-1/2 Inch Fine 3/16" - 1/2" Whitworth Tungsten Alloy Steel Taper, Plug Taps Dies:3/16" X 32, 1/4" X 26, 5/16" X 22, 3/8" X 20, 7/16" X 18, 1/2" X 16 Bsf Tap Holder For M3 M12 (1/16" 1/2") Length 200Mm Die Holder For Dies With 25Mm (1") Diameter, Length 200Mm.
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