This International Standard specifies the characteristics of hexagon head screws with threads from M1.6 up to and Including M64, of product grade A for threads M1.6 to M24 and nominal lengths up to and including 10 d or 150 mm, Whichever is shorter, and product grade B for threads over M24 or nominal lengths over 10 d or 150 mm, whichever is shorter.

Commercially, the steel quality used to manufacture of the ISO 933 grade 8.8 bolts includes Grades A2 and A4 class 70 . The tensile strength for both these steel grades is around 700 Mpa. The strength of the ISO933 bolt M10x18 is indicated by the marking on the head and it is also defined by the applicable product standard. The A2 version of theISO933 bolt material is manufactured from Stainless Steel grade 304, which is known for its Corrosion Resistant properties.

This can be attributed to the high content of chromium and nickel in the alloy of the ISO 933 bolt M8x15 (Metallurgically, the A2 or the ASTM-304 has a designation of 18/8 Stainless Steel or 18% Chromium & 8% Nickel). Although the A2 is mostly considered to be a non-magnetic austenitic stainless steel grade, some residual magnetism of the alloy can be introduced when the material of the IS O933 Bolts are cold worked.

Similar to the A2, the A4-70 ISO 933 bolt material specification is an austenitic, acid proof stainless grade. Usually, the A4-70 is manufactured from stainless steel grade 316 material or its low carbon variant grade 316L. stainless steel grade 316 has been cold worked to provide a minimum tensile ISO933 bolt strength of 700 MPa.

As compared to stainless steel grade 304, grade 316 provides better overall corrosion resistant properties. This holds true particularly as grade 316 stainless steel has a higher resistance to both pitting as well as crevice corrosion in chloride environments. The good corrosion properties of the ISO933 hex bolt manufactured from Grade 316 stainless steel can be attributed to the high molybdenum content in its alloy.