Diameter Thread Threads Length Grade Finish Weight
0.2500 (1/4) Partial 20 0.6250 (5/8) GR 8 Plain Finish 0.0116
Diameter 0.2500 (1/4)
Thread 20
Length 0.6250 (5/8)
Grade GR 8
Finish Plain Finish
Weight 0.0116

  • GR 8
  • Alloy Steel

Place Bolts — otherwise known as Locking Head Bolts, GM Lock Bolts, or Type AA Lock Bolts are specially designed to provide a locking action between the bolt and the material being clamped. The locking comes from the crevice under the head and the slots in the top causing the head to flex as it’s tightened. These bolts are well known for their use in transition and diesel engines and many other capacities.

Place Bolt – Grade 8

  • The flexing of the bolt prevents the bolt from loosening in high-vibration applications
  • The bolt provides a locking action between the head of the bolt and the material being clamped
  • The specially designed head gives the ability to flex, providing additional elastic elongation not developed by standard hex head cap screws
  • The 5/8 and 3/4 diameters have one wrench size smaller head than the standard, allowing clearance in tight applications
  • Rockwell hardness of Rc 33/39
  • Tensile strength of 150,000 psi
  • Width across flats range from 1/4" to 3/4”
  • Meets GM Type AA standards

    • Support 1-800-327-6378