S-99926A142 1/4"-20 x 1 1/4" Stainless Steel Hex Drive Flat Head Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with 18-8 stainless steel construction and passivated finish, ideal for harsh industrial environments
• High-strength performance with 70,000 psi tensile strength and Rockwell B70 hardness for reliable load-bearing applications
• Precise thread engagement thanks to Class 3A UNC coarse thread fit, ensuring secure fastening and vibration resistance
• Efficient installation with hex drive design and 1/8" drive size, providing excellent torque transmission and reduced cam-out risk
• Flush mounting capability featuring undercut flat head profile and 100° countersink angle for seamless surface integration
• Optimized thread design with partial threading and 1.11" minimum thread length for controlled clamping force distribution
• Regulatory compliance meeting RoHS 3 and REACH standards for environmentally responsible manufacturing

Professional Applications & Engineering Value

Engineered for demanding industrial applications, this 18-8 stainless steel flat head screw combines material excellence with precision manufacturing to solve critical fastening challenges. The passivated finish significantly enhances corrosion resistance in moisture-prone environments, while the Class 3A UNC coarse thread ensures rapid installation and superior vibration resistance in machinery, equipment assembly, and structural frameworks. The hex drive design provides maximum torque transmission without slippage, and the undercut flat head profile with 100° countersink angle creates seamless flush mounting for applications where surface clearance is critical. With 70,000 psi tensile strength, this fastener maintains integrity under substantial mechanical stress, making it ideal for automotive, manufacturing, and construction applications requiring reliable, long-term performance.

Specification Summary & Compliance

This 1/4"-20 UNC flat head screw features Class 3A thread fit precision with coarse thread spacing, ensuring consistent performance across industrial applications. The fastener maintains dimensional accuracy with specified head diameter (0.531"), head height (0.105"), and minimum thread length (1.11"). Manufacturing compliance includes adherence to RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations, confirming the absence of restricted substances. The combination of material specifications (18-8 stainless steel), mechanical properties (70,000 psi tensile strength, Rockwell B70 hardness), and surface treatment (passivated finish) ensures consistent performance meeting industrial fastener standards.