In response to market demand, Hill Fastener now offers - and stocks - these high-strength bolts in common sizes, in both course and fine threads.

Grade-8 Undercut Hex Flange Screws ("Frame Bolts")

Formed from high grade alloy steel and heat treated to SAE Grade-8 mechanical requirements, these screws are dimensioned to IFI-111 specifications with the additional feature of a recessed fillet radius, or "undercut." They are stocked in popular lengths in 3/8", 1/2" and 5/8" diameters in both course and fine thread in either Phosphate & Oil or Plated & Baked finishes.

Key Benefits

• Burrs from punched or drilled holes do not interfere with the bearing surface of the screw; therefore the holes do not have to be as precise or reamed out before inserting a bolt.
• A uniform mating surface provides a low stress to high clamp load ratio.
• The increased clamp load is distributed over a wider area, providing improved joint integrity, when used with a hex flange nut.