S-91355A186 1/4"-28 x 3/4" Steel Flanged Button Head Hex-Drive Screws

Key Features & Benefits at a Glance

• Exceptional corrosion resistance with black-oxide coating, extending service life in demanding industrial environments
• Precise Class 3A thread fit ensures reliable, vibration-resistant connections in critical assemblies
• High 120,000 psi tensile strength provides superior load-bearing capacity for heavy-duty applications
• Convenient hex drive design with 5/32" drive size enables quick installation and secure torque transmission
• Integrated flange design eliminates need for separate washers, simplifying assembly and reducing component count
• Full threading along 3/4" length offers maximum grip range and adjustment flexibility
• Rockwell C32 hardness maintains thread integrity and prevents stripping during repeated use

Professional Applications & Engineering Value

Engineered for precision industrial applications, these black-oxide alloy steel rounded head screws solve critical fastening challenges where vibration resistance and corrosion protection are paramount. The UNF fine thread configuration (1/4"-28) provides superior holding power in metals and engineered materials, while the Class 3A thread fit ensures consistent clamping force in automated assembly environments. The combination of 120,000 psi tensile strength and Rockwell C32 hardness makes these flanged hex drive screws ideal for machinery, equipment manufacturing, and structural applications requiring reliable, high-strength fasteners that withstand dynamic loads and harsh operating conditions.

Specification Summary & Compliance

This precision fastener meets UNF thread standards with Class 3A fit for superior dimensional accuracy. Manufacturing complies with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations. The screw features fully threaded design with 0.563" flange diameter and right-hand thread direction, manufactured from high-grade alloy steel with controlled hardness and strength specifications.