S-91253A638 3/8"-16 x 3 1/4" ASTM F835 Alloy Steel Hex Drive Flat Head Screws

Key Features & Benefits at a Glance

• Exceptional tensile strength of 130,000 psi ensures reliable performance in demanding applications, reducing the risk of fastener failure.
• Black-oxide finish on alloy steel provides enhanced corrosion resistance, extending service life in harsh industrial environments.
• Class 3A thread fit offers superior precision and secure fastening, minimizing the chance of loosening under vibration.
• Partially threaded design allows for controlled clamping force, ideal for applications requiring precise joint compression.
• 82° countersink angle ensures a flush fit with standard countersunk holes, providing a smooth surface finish and improved aesthetics.
• Hex drive (7/32") enables high-torque installation with common tools, speeding up assembly and reducing labor time.
• Rockwell C39 hardness delivers excellent wear resistance, maintaining thread integrity through repeated use.

Professional Applications & Engineering Value

These 3/8"-16 UNC flat head screws are engineered to address critical challenges in industrial assembly, where vibration resistance, high strength, and environmental durability are paramount. The black-oxide alloy steel construction combats rust and wear, making them suitable for machinery, automotive, and structural applications exposed to moisture or chemicals. The coarse UNC threading and Class 3A fit provide quick, secure engagement in metals and composites, reducing installation errors. With a partially threaded shank, they allow for precise clamping without over-tightening, preventing material damage. Ideal for heavy-duty fastening in construction and manufacturing, these screws ensure long-term reliability under 130,000 psi tensile loads, meeting the rigorous demands of professional engineers and maintenance teams.

Specification Summary & Compliance

This product adheres to Class 3A thread fit for high precision and UNC coarse thread standards (3/8"-16). Manufacturing complies with ASTM F835 specifications, ensuring consistent quality and performance. It is fully RoHS 3 (2015/863/EU) Compliant and REACH (EC 1907/2006) Compliant, supporting environmental and safety regulations for global industrial use.