S-91253A317 1/4"-28 x 1 3/4" ASTM F835 Alloy Steel Hex Drive Flat Head Screws
Alloy Steel Hex Drive Flat 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 corrosion resistance with black-oxide coating, ideal for harsh industrial environments
- Superior load-bearing capacity from 130,000 psi tensile strength and Rockwell C39 hardness
- Precise thread engagement with Class 3A fit and UNF fine threading for vibration-resistant connections
- Optimized flush mounting featuring 82° countersink angle and standard flat head profile
- Secure installation control through 5/32" hex drive preventing cam-out during torque application
- Reliable partial threading design providing enhanced clamping force in designated engagement zones
- Full regulatory compliance meeting ASTM F835, RoHS 3, and REACH standards for global applications
Professional Applications & Engineering Value
These black-oxide alloy steel flat head screws deliver critical performance advantages in precision assemblies where surface flushness and corrosion resistance are paramount. The 1/4"-28 UNF fine threading with Class 3A fit ensures superior vibration resistance in machinery, automotive, and aerospace applications where loosening under dynamic loads presents significant failure risks. The combination of 130,000 psi tensile strength and controlled partial threading provides optimal clamp load distribution while the 82° countersink angle enables seamless integration in precision-machined components. The black-oxide surface treatment extends service life in humid or chemically aggressive environments without compromising dimensional stability.
Specification Summary & Compliance
Manufactured to exacting Class 3A thread tolerances with UNF (Unified National Fine) thread form and 1/4"-28 specification. Complies with ASTM F835 standard for alloy steel hex drive screws, demonstrating full conformance to RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations. Threading extends minimum 1" with overall 1 3/4" length, featuring right-hand thread direction and Rockwell C39 hardness certification.
