Some of the frequently asked question we get asked are presented below:


  • Why use Grade 10.9 over Grade 8.8?

       10.9 Grade is 25% stronger which makes it more suitable for heavy duty application where strength performance is critical.


  • How are fasteners measured?

       Fasteners are measured by diameter, length, and thread count. Diameter is how wide the shaft of the screw is.

       Diameter is usually measured outside the thread. Thread count is measured by TPI (thread per inch). The smaller the fastener

       the finer the thread. The length of a fastener is measured by its shank generally, the head is excluded. In the case of

       countersunk fasteners, the length is measured from the head including the shank.



Measuring a bolt

M10- Diameter in mm, 33- Length of bolt in mm, 1.25- Thread pitch

Measuring a countersunk screw

  • DIN931Bolt/DIN933 Bolt – What are the differences?

       DIN931 Hex Head is a Thread Bolt

       DIN933 Hex Head is a Thread Bolt

  • What are the marks showing on the head of a bolt?


       The majority of fasteners have head marking with the manufactures logo on them plus the bolt strength i.e. 8.8/10.9/12.9 {A2} {A4}



  • What Types of fastener materials are there?


       Steel Fasteners:

       Steel fasteners are commonly available in 4 grades.

       Stainless Steel & Aluminum:

       These materials are inherently resistant to corrosion. The strength of stainless is much less than alloy steel, and even less so

       for aluminum.

       Bronze and Brass:

       Bronze has high corrosion resistance quality. It is suitable for aquatic applications, such as underwater construction.

       Brass is somewhat similar to bronze in its anti-corrosive properties, but with slightly lower tensile strength because it

       is comparatively softer.

       Black Oxide:

       This provides very low protection against corrosion and usually coated with an oil film for extra protection.

       Hot-Dipped Galvanized:

       After stainless steel, this provides the best protection for outdoor use.