S-91355A153 4-40 x 1/4" Steel Flanged Button Head Hex-Drive Screws

Key Features & Benefits at a Glance

• Exceptional tensile strength of 120,000 psi ensures reliable performance in demanding applications
• Precision Class 3A thread fit provides superior engagement and vibration resistance
• Black-oxide coating on alloy steel offers enhanced corrosion protection and durability
• Integrated flange design eliminates the need for separate washers and distributes load evenly
• Hex drive configuration allows for secure tool engagement and efficient installation
• Fully threaded construction maximizes holding power across the entire fastener length
• Rockwell C32 hardness maintains structural integrity under heavy mechanical stress

Professional Applications & Engineering Value

These 4-40 UNC Class 3A rounded head screws deliver critical performance advantages in industrial assembly environments. The black-oxide alloy steel construction provides superior corrosion resistance while maintaining the 120,000 psi tensile strength required for heavy-duty applications. The coarse UNC thread design ensures rapid installation and reliable performance in materials where fine threads might strip or fail. The combination of fully threaded construction and integrated flange creates a versatile fastener that eliminates the need for additional components while providing superior clamping force. These industrial screws are particularly valuable in machinery assembly, electronic enclosures, and automotive components where vibration resistance and consistent performance are paramount.

Specification Summary & Compliance

This rounded head screw features precision 4-40 UNC Class 3A threads with right-hand orientation and coarse spacing. The fastener meets exacting dimensional standards with a 1/4" length and 0.234" flange diameter. Manufacturing compliance includes RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations, ensuring suitability for global industrial applications requiring strict material restrictions.