S-91251A110 4-40 x 1/2" ASTM A574 Alloy Steel Socket Head Screws
Alloy Steel Socket Head Screws
Image may differ from product. See technical specification for details.
Basic Information
Head Parameters
Dimensions
Thread Parameters
Tip & Drive Parameters
Material & Strength
Temperature & Environment
- Fast delivery
- Enjoy discounts on bulk purchases
- Secure Payment
- Fast Global Shipping
Key Features & Benefits at a Glance
- Exceptional tensile strength of 170,000 psi ensures reliable performance under high-stress conditions, reducing the risk of fastener failure.
- Superior corrosion resistance from the black-oxide finish on alloy steel, extending service life in demanding industrial environments.
- Precision Class 3A thread fit provides tighter tolerances for secure, vibration-resistant assemblies with minimal backlash.
- Hex socket drive design allows for high-torque installation in confined spaces, improving assembly efficiency and tool accessibility.
- Fully threaded right-hand coarse UNC pattern enables faster installation and stronger holding power in a wide range of materials.
- Consistent hardness (Rockwell C37) maintains dimensional stability and wear resistance over repeated use cycles.
- Compliance with ASTM A574, RoHS 3, and REACH ensures material quality and environmental safety for global supply chain integration.
Professional Applications & Engineering Value
Engineered for high-performance industrial assemblies, these 4-40 UNC socket head cap screws address critical challenges in precision machinery, automotive components, and electronic enclosures. The black-oxide alloy steel construction combats oxidation and wear, while the coarse thread design enhances engagement in softer substrates or plated materials. With a fully threaded right-hand configuration and hex drive compatibility, they simplify maintenance and reduce installation time in space-constrained applications. Ideal for high-vibration environments, these fasteners deliver reliable clamping force and repeatable performance, minimizing downtime and ensuring long-term operational integrity.
Specification Summary & Compliance
This fastener adheres to inch system measurements with a 1/2" length and Class 3A thread fit per UNC standards, ensuring precise dimensional accuracy. Manufacturing follows ASTM A574 specifications for alloy steel socket head cap screws, guaranteeing consistent mechanical properties. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, confirming the absence of restricted substances for safe use in regulated industries.
