A SAE bolt head has 3 slashes or raised marks. These marks indicate a ___ bolt.

A SAE bolt head has 3 slashes or raised marks. These marks indicate a ___ bolt.

• A. Grade 8
• B. Grade 5
• C. Grade 2
• D. Grade 10.9

Answer: (B)

Bolt head markings show the bolt’s grade and strength. Three raised lines on the head identify a Grade 5 SAE bolt, which is a medium-strength option used when more strength than Grade 2 is needed but not as strong as Grade 8. Grade 2 bolts typically have no markings, and Grade 8 bolts have more marks (often six). The option mentioning Grade 10.9 refers to a metric grade and is indicated differently on the head, not by three slashes. So the three slashes point to Grade 5.

Bolt head markings show the bolt’s grade and strength. Three raised lines on the head identify a Grade 5 SAE bolt, which is a medium-strength option used when more strength than Grade 2 is needed but not as strong as Grade 8. Grade 2 bolts typically have no markings, and Grade 8 bolts have more marks (often six). The option mentioning Grade 10.9 refers to a metric grade and is indicated differently on the head, not by three slashes. So the three slashes point to Grade 5.