S-91266A650 3/8"-24 x 3/4" ASTM F835 Alloy Steel Thread-Locking Hex Drive Flat Head Screws

Key Features & Benefits at a Glance

• Vibration-resistant locking performance with permanent Nylon patch that maintains integrity across -65° to 250°F temperature range
• Exceptional tensile strength at 130,000 psi ensures reliable fastening in high-stress industrial applications
• Precision Class 3A thread fit provides superior engagement and consistent clamping force in critical assemblies
• Corrosion-resistant black-oxide finish on alloy steel base material enhances durability in demanding environments
• Standard 82° countersink angle allows for flush mounting in precision-machined components
• Hex drive design (7/32") enables secure tool engagement and efficient installation in confined spaces
• Full threading along 3/4" length ensures maximum thread engagement and load distribution

Professional Applications & Engineering Value

This high-strength 3/8"-24 UNF flat head screw addresses critical vibration-induced loosening challenges in industrial machinery, automotive systems, and precision equipment. The permanent Nylon patch thread locker provides reliable locking performance without compromising the Class 3A thread fit precision, ensuring maintained clamp load in dynamic applications. The black-oxide alloy steel construction combined with Rockwell C39 hardness delivers exceptional wear resistance while the fine thread spacing enables precise adjustment in thin-section materials. Engineered for applications requiring both flush mounting capabilities and vibration resistance, this fastener eliminates the need for secondary locking components while meeting rigorous ASTM F835 performance standards.

Specification Summary & Compliance

This precision fastener features Class 3A thread fit with 3/8"-24 UNF fine threads and full threading along the 3/4" length. Manufacturing complies with ASTM F835 specifications, ensuring consistent quality and performance. The product is RoHS 3 (2015/863/EU) compliant and REACH (EC 1907/2006) compliant for environmental responsibility. The 82° countersink angle conforms to standard flat head profiles, while the hex drive (7/32") provides secure tool engagement during installation.