What does "Grade 8" indicate for a bolt?

• A. It indicates decorative finish.
• B. High tensile strength/hardness and suitability for high-strength applications.
• C. It indicates corrosion resistance only.
• D. It indicates the bolt is reusable without threads.

Answer: (B)

Strength ratings on bolts indicate how much load and how much hardness the fastener can reliably handle, guiding you to pick the right one for demanding duties. Grade 8 is a high-strength designation, meaning the bolt is made from alloy steel and heat-treated to achieve a high minimum ultimate tensile strength and hardness. This makes it well-suited for high-strength applications where you need strong clamping and resistance to stretch under heavy load. It’s designed to work with compatible Grade 8 nuts and washers and requires proper torque to achieve the intended clamping force. The grade doesn’t specify decorative appearance or corrosion resistance by itself, and it doesn’t imply the bolt can be reused without threads.