Bolt Heads

We are curious about what makes each bolt unique. We want to help you become more knowledgeable about bolts, threads & fasteners! Each bolt has its own special markings to make it easy to identify.

For instance, did you know that bolt heads have different identifications?

• 3 lines- Gr. 5 bolts
• 6 lines-Gr. 8 bolts
• 10.9- metric bolts (equivalent to Gr. 8 bolts) 
• 8.8- metric bolts (equivalent to Gr. 5 bolts)