S-91273A304 1/4"-20 Shoulder Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with 18-8 Stainless Steel construction, ideal for harsh industrial environments and extended service life.
• Precise component alignment ensured by the standard shoulder fit and controlled diameter/length tolerances, reducing assembly errors.
• High mechanical strength offering 70,000 psi tensile strength and 35,000 psi shear strength for reliable performance under load.
• Secure, non-slip fastening provided by the knurled head and hex socket drive, allowing for high-torque installation.
• Easy assembly and interchangeability with standard 1/4"-20 UNC coarse threads and Class 2A fit, compatible with common nuts and tapped holes.
• Enhanced durability from a Rockwell B55 hardness, resisting wear and deformation in demanding applications.
• Compliance with global environmental standards including RoHS 3 and REACH, ensuring safe and sustainable use.

Professional Applications & Engineering Value

This stainless steel shoulder screw is engineered to solve critical alignment and pivot point challenges in machinery and assemblies. The 1/4"-20 UNC thread with coarse spacing and Class 2A fit ensures quick, secure fastening, while the precisely machined shoulder provides a stable bearing surface for gears, linkages, and rotating parts. Made from 18-8 Stainless Steel, it resists rust and corrosion in moist or chemical-exposed environments, making it ideal for industrial applications like automotive jigs, conveyor systems, and electronic enclosures. The hex socket head with knurling allows for high-torque installation in confined spaces, reducing the risk of stripping and improving maintenance efficiency. This combination of high tensile strength and dimensional accuracy delivers reliable performance, minimizing downtime and ensuring long-term operational integrity.

Specification Summary & Compliance

This shoulder screw adheres to UNC thread standards with a Class 2A thread fit for consistent engagement. Key dimensions include a 1/4" shoulder diameter (tolerance: -0.004" to -0.002") and 1" shoulder length (tolerance: -0.005" to 0.005"), ensuring precise alignment. It is manufactured to meet RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) compliance, supporting environmentally responsible sourcing and use in regulated industries.