Fastener attributes

Bulten offers a wide portfolio of different product types with various attributes.


The ISO metric thread system is the dominating system to which we produce our products. The inch based unified system still exist, but is slowly phased out.

M4 to M24



The dominating material for our products is martensitic steels according to ISO898-1, in the higher strength grades. However, we also offer stainless steel and heat resistant fasteners and have the capability to developing non-ferrous products upon request.

8.8, 10.9 and 12.9
Stainless A4-80 & A2-70
Heat resistant (A286)


Head types

The fastener industry is dominated by a few standardized drive types; hexagon, 12-point and Torx. We offer these drive types in a multitude of head shapes such as flange, cylindrical or pan head designs as well as completely tailor made head designs to customer request.

Hexagon head
Hexagon flange head
Torx flange head
Pan head
Cylindrical head hexagon socket
Cylindrical head torx

head types

Surface coatings

Almost all fasteners supplier by Bulten have a surface coating. Surface coatings are applied primarily as corrosion protection and to create a stable assembly friction, but there are decorative coatings as well where the corrosion protection is not the primary purpose.

Zinc flake coatings

surface coating