Description
Straight flute hand tap NO1 with a 6-8xP taper lead, for British Standard Whitworth thread BSW 5/16″ with 18 TPI and Medium class of fit, dimensions according to ISO 529 standard with 8.0mm shank and 6.3mm square drive, HSS with bright finish for 1.5xD through or blind hole threading in free machining and plain carbon steel and copper or copper alloys
