S-99904A104 1/2"-13 Flange Nuts

Key Features & Benefits at a Glance

• Superior vibration resistance through precision-engineered serrations that provide permanent locking, preventing loosening in high-stress environments
• Enhanced load distribution with 1 1/32" flange diameter that reduces surface pressure and prevents damage to connected materials
• Exceptional strength and durability from Grade 5 steel construction, capable of withstanding heavy-duty industrial applications
• Reliable corrosion protection through zinc-plated surface treatment that extends service life in demanding conditions
• Easy installation and removal with standard external hex drive design compatible with common wrench tools
• Precise thread engagement with Class 2B thread fit ensuring consistent performance and reduced cross-threading risks
• Environmental compliance assurance meeting both REACH and RoHS 3 standards for safe industrial use

Professional Applications & Engineering Value

This Grade 5 zinc-plated steel flange lock nut delivers critical vibration resistance in demanding applications where safety and reliability are paramount. The serrated locking design bites into mating surfaces, creating permanent resistance to rotational forces that cause conventional nuts to loosen over time. Engineered with UNC coarse threads and Class 2B thread fit, this heavy-duty fastener maintains precise tolerances while accommodating minor surface imperfections. The integrated 1 1/32" flange eliminates the need for separate washers, distributing clamp load over a wider area to prevent material damage. Ideal for heavy machinery, automotive assemblies, structural frameworks, and industrial equipment, this external hex drive nut combines installation efficiency with long-term performance security in vibration-prone environments.

Specification Summary & Compliance

This flange lock nut features 1/2"-13 UNC coarse threads with Class 2B thread fit tolerances, ensuring reliable engagement with mating components. The standard hex profile with 3/4" width and 29/64" height provides optimal tool engagement. Manufactured from zinc-plated steel with a 1 1/32" flange diameter and 0.05" flange thickness, the nut delivers consistent performance across industrial applications. The product is fully compliant with REACH (EC 1907/2006) and RoHS 3 (2015/863/EU) environmental standards, meeting the latest regulatory requirements for industrial fasteners.