Thread data BSW, BSF, BSP 55°; BA Tread Form - Angle of thread = 47. 5 degrees, rounded at top and bottom BA
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XYWHPGV Machine Tap 1/2-12 BSW Thread Pitch 4 Straight Flutes H2 High Speed Steel(3eab0 48a91 6ef68 9e5e8 dd1eb 30aa3 : Amazon.co.uk: Everything Else
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