S-90337A394 4-40 Shoulder Screws

Key Features & Benefits at a Glance

• Exceptional corrosion resistance with 18-8 stainless steel and passivated finish, ideal for harsh environments
• Precise alignment and reduced wear due to the exact 1-1/2" shoulder with tight tolerances for stable component positioning
• High strength-to-weight ratio offering 70,000 psi tensile strength and Rockwell B55 hardness for reliable load-bearing
• Space-saving low-profile socket head with hex drive for easy installation in confined areas without compromising torque
• Consistent threading performance with UNC coarse threads and Class 2A fit ensuring secure fastening and vibration resistance
• Broad regulatory compliance including RoHS 3 and REACH, meeting strict international environmental and safety standards
• Durable right-hand thread design for standard applications, enhancing longevity in repetitive assembly operations

Professional Applications & Engineering Value

This 4-40 UNC shoulder screw is engineered to address common industrial challenges such as misalignment and component slippage in precision machinery. The 1-1/2" shoulder with minimal tolerances provides a stable pivot or axle, reducing wear in rotating assemblies like bearings and linkages. Made from 18-8 stainless steel with a passivated finish, it resists corrosion in moist or chemical-laden settings, extending service life in automotive, aerospace, and electronics manufacturing. The low profile socket head and hex drive allow for secure tightening in tight spaces, while the coarse UNC threads ensure quick, reliable fastening, minimizing downtime in high-volume production lines.

Specification Summary & Compliance

This shoulder screw adheres to UNC thread standards with a Class 2A fit for consistent dimensional accuracy. The shoulder diameter is precisely maintained at 1/8" with a tolerance of -0.001" to 0", and the shoulder length is 1-1/2" with a tolerance of 0" to 0.002" for reliable performance. It complies with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring environmental safety and material restrictions are met for global industrial use.