Machine Tap, ≈ DIN 371, HSS-E, UNC 5/16 x 18 

for general use - non abrasive material up to 900 N/mm² - unalloyed and low alloyed steel - for blind holes Thread type: Unified Coarse thread ANSI B 1.1 Norm: ≈ DIN 371 Material: HSS-E