US TAP AND DRILL BIT SIZE

Head MarkingClass & MaterialsSize Range (mm)Mechanical Properties
Proof Load (MPa)
Mechanical Properties
Min. Yield Strength (MPa)
Mechanical Properties
Min Tensile (MPa)
8.8_MarkingClass 8.8
Medium Carbon Steel
Below 16mm

16mm-72mm
580

600
640

660
800

830
10.9_MarkingClass 10.9
Alloy Steel
5mm-100mm8309401040
12.9_MarkingClass 12.9
Alloy Steel
1.6mm-100mm97011001220
a2_marking

Stainless Steel
Markings Vary
Usually stamped A-2
A-2 Stainless
Steel Alloy with
17-19% Chromium &
8-13% Nickel
Up to 20mm-210 Min.
450 Typical
500 Min.
700 Typical