EX311/4 UNF Machine Tap Spiral Flute 45°

Spiral flute tap with chamfer form C with a 2-3xP plug lead, for Unified National Fine thread UNF 1/4" with 28 TPI and 2B class of fit, dimensions according to DIN 2184-1 standard with 7.0mm shank and 5.5mm square drive, powder metallurgical HSS-E with steam tempered surface finish and 45° helix angle for 2.5xD blind hole threading in alloy steel