S-99291A550 1/4"-20 Locknuts
Locknuts
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Basic Information
Dimension Parameters
Thread Parameters
Head Parameters
Material & Strength Parameters
Installation & Application Parameters
Finish & Compliance Parameters
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Key Features & Benefits at a Glance
- Superior vibration resistance through distorted thread top-lock technology, preventing loosening in high-stress applications
- Enhanced corrosion protection with zinc-flake coating, extending service life in harsh industrial environments
- Reliable mechanical performance meeting ASTM Grade C strength requirements for heavy-duty applications
- Precision thread engagement with Class 2B fit ensuring consistent clamping force and assembly security
- Standard external hex drive design for compatibility with common tools and efficient installation
- Compliance with environmental regulations including RoHS 3 and REACH standards for global market acceptance
- Optimized dimensional stability with 7/16" width and 7/32" height for space-constrained assemblies
Professional Applications & Engineering Value
This 1/4"-20 UNC coarse thread locknut delivers critical vibration resistance where conventional fasteners fail. The distorted thread top-lock mechanism creates permanent friction along the mating surface, eliminating the need for secondary locking devices in industrial machinery, automotive systems, and heavy equipment. Manufactured from zinc-flake-coated steel, it provides exceptional barrier protection against corrosion while maintaining ASTM Grade C mechanical properties. The Class 2B thread fit ensures precise engagement with mating components, reducing installation torque variations and preventing cross-threading in high-volume production environments. Engineered for reliability in dynamic loading conditions, this external hex locknut combines installation convenience with long-term performance security.
Specification Summary & Compliance
This locknut features 1/4"-20 UNC coarse threads with Class 2B thread fit tolerance for precision engagement. The distorted thread top-lock design conforms to industrial locking standards while the zinc-flake-coated steel construction meets ASTM Grade C strength requirements. Dimensions include 7/16" width across flats and 7/32" height. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations, ensuring global market acceptance and sustainable manufacturing practices.
