Each bolt is made from a 3-D model generated from our coordinate measuring machine (CMM) with machining tolerances of .05mm (.002in). Machined out of billet 4140 steel alloy. 

Heat treated to a hardness of Rockwell C37, guaranteed to never wear out.

Our quality control department inspects all of the bolts and fits them to a TD04 turbo to ensure accuracy before our shipping department cleans, sanitizes, and seals the items in an airtight plastic pouch.