External Hexagon Drive

Bolts and Screws are available in strength grades   4.6   8.8   10.9   and  12.9

hexagon bolt hexagon cap hex 10.9        HEX 12.9  

It is obligatory that the strength grade and manufacturer’s identification be shown on the head of the fastener.



External Hexagon Drive

External Hexagon Drive is the traditional open spanner drive using a six-sided fastener head. The fastener is known as a Hexagon head cap screw in America, in the UK and Europe it is known as a hexagon head bolt. The hexagon drive is better than external square drive for locations where surrounding obstacles limit wrenching spanner access, 

Most hexagon cap screws (bolts) are partially threaded, the exception is on shorter lengths; fully threaded hexagons are called Tap bolts in America and hexagon set screws in the UK and Europe.


Metric specifications Europe


DIN 931 bolt  933 set screw din 960 din 961  din 6914


All have hexagon heads are naturally finish is black oiled after heat treatment, Bolts and Screws are often Zinc plated by the manufacturer or the distributor.




Inch specifications USA UNC  UNF


GRADE 5 SAE J429 ASTM A449-93 Rockwell C25-34  (8.8)

sae 5 hex cap 

GRADE 8 SAE J429 ASTM A354 BD Rockwell C33-39  (10.9)