July 2015 Kit of the Month – Grade 8 Standard Cap Screw Kit

72B12 Metal Stand Up Storage Bin

This month we are featuring our Grade 8 Standard Cap Screw Kit.

We are proud to offer a full line of Grade 8 cap screws MADE IN THE USA.

Where are Grade 8 cap screws used?

Common uses for grade 8 bolts include military, aerospace, or marine-related mechanical applications where high stress and strong load bearing pressures are a major factor. The off road vehicle market also has a need for grade 8 bolts for the same reasons. One thing to keep in mind is when in doubt, it’s almost always a safer bet to go with the highest grade of bolt you can. Manufacturers may recommend a grade 5 but it never hurts to go with higher quality materials.

Grade 8 cap screws product information:

A grade 8 bolt is stronger than the more commonly used grade 5. It is made of alloy steel and has six radial lines on the top of the bolt head. Grade 8 bolts have a tensile strength of 150,000 pounds per square inch. We recommend using grade 8 nuts, flat washers and high alloy lock washers with any grade 8 bolts / hex cap screws.



Radial Bolt Markings


Nominal Size

Proof Load

Tensile Strength
minimum psi

Yield Strength

minimum psi

Grade 8
6 Radial Lines
Grade 8 Radial Bolt Markings - 6 Radial Lines Medium Carbon Alloy Steel 1/4″ through 1/2″ 120,000 150,000 130,000


July 2015 Kit of the Month

Grade 8 Standard Cap Screw Kit

$499.00 each Order Now!



  • Screws, hex nuts, flat and lock washers in sizes: 1/4″, 5/16″, 3/8″, 7/16″, and 1/2″

Click here to view the contents of this kit

Click to play the video below to learn more