IFI 100/107 Top Locknut Grade C 1/2-13
(Pack of 50)

Tuff-Torq®

The Top Locknut Grade C delivers uncompromising reliability when your high-stress applications demand it most. This heat-treated, vibration-resistant locknut maintains its grip through severe conditions that would cause standard nuts to fail, ensuring your critical assemblies stay secure even under extreme vibration and repeated stress cycles. Engineered specifically for Grade 8 applications, it retains its locking torque through a minimum of five reapplications while meeting stringent IFI and ANSI specifications with 150,000 PSI minimum proof strength. Whether you're working on heavy machinery, automotive assemblies, or industrial equipment, this Grade C locknut provides the dependable hold that keeps your work running smoothly and safely.
• Heat-treated for matched strength
• Will not loosen even under severe vibration
• Locking torque is retained for a minimum of five reapplications
• 150,000 PSI minimum proof strength
• Meets IFI and ANSI specifications
• Developed for Grade 8 applications
• Designed for use with Tuff-Torq® Cap Screws
• Identified by six symmetrically spaced marks on the chamfered surface on the top of the nut
NOTE: Not recommended for use above 450°F (232°C).
For recommended torque values, see Lawson’s E546 brochure.

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Product Description

The Top Locknut Grade C delivers uncompromising reliability when your high-stress applications demand it most. This heat-treated, vibration-resistant locknut maintains its grip through severe conditions that would cause standard nuts to fail, ensuring your critical assemblies stay secure even under extreme vibration and repeated stress cycles. Engineered specifically for Grade 8 applications, it retains its locking torque through a minimum of five reapplications while meeting stringent IFI and ANSI specifications with 150,000 PSI minimum proof strength. Whether you're working on heavy machinery, automotive assemblies, or industrial equipment, this Grade C locknut provides the dependable hold that keeps your work running smoothly and safely.
• Heat-treated for matched strength
• Will not loosen even under severe vibration
• Locking torque is retained for a minimum of five reapplications
• 150,000 PSI minimum proof strength
• Meets IFI and ANSI specifications
• Developed for Grade 8 applications
• Designed for use with Tuff-Torq® Cap Screws
• Identified by six symmetrically spaced marks on the chamfered surface on the top of the nut
NOTE: Not recommended for use above 450°F (232°C).
For recommended torque values, see Lawson’s E546 brochure.

Technical Specifications

Item#: 80931
Diameter 1/2 "
Thread Pitch 13
Grade C
Finish Zinc/Wax
Type Top Lock Nut
Material Alloy Steel
Thickness 0.573 "
Across Flats 3/4 "
Thread Coarse
Size 1/2-13
Specifications IFI 100/107
Maximum Temperature 450º F
Proof 150,000 PSI
UNSPSC #: 31161716
TAA Compliant: No
Weight: 1.71 lb

Product Restrictions

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