S-91273A157 1/4"-20 Shoulder Screws

Key Features & Benefits at a Glance

• Enhanced Durability in Harsh Environments – 18-8 stainless steel construction provides excellent corrosion resistance, ensuring long-term reliability in demanding industrial settings.
• Superior Tensile and Shear Strength – With 70,000 psi tensile strength and 35,000 psi minimum shear strength, this screw withstands high-stress applications without failure.
• Precision Thread Fit for Secure Assembly – Class 2A thread fit ensures consistent, reliable engagement, reducing the risk of loosening under vibration or load.
• Easy Installation and Removal – Hex socket drive and knurled head texture offer improved grip and torque application, speeding up assembly and maintenance.
• Stable Shoulder for Accurate Alignment – The 3/8" shoulder length with tight diameter tolerance provides precise component positioning and rotational stability.
• Broad Regulatory Compliance – Meets RoHS 3 and REACH standards, making it suitable for use in regulated industries and international markets.
• Optimized for Coarse Thread Applications – 1/4"-20 UNC coarse thread facilitates quicker assembly and better performance in materials where fine threads may strip.

Professional Applications & Engineering Value

This socket head shoulder screw is engineered to address critical alignment and load-bearing challenges in machinery and equipment. The 18-8 stainless steel material offers robust corrosion resistance, ideal for environments exposed to moisture, chemicals, or temperature variations. The 3/8" shoulder length and precise shoulder diameter provide a stable pivot or bearing surface, essential in assemblies requiring exact component spacing—such as in rotating shafts, linkages, or precision instruments. The hex socket drive and knurled head texture enhance torque transmission and handling efficiency, reducing installation time and tool slippage. With a Class 2A thread fit and UNC coarse thread, it ensures rapid, secure fastening in metals and plastics, minimizing cross-threading risks. These features make it a reliable choice for automotive, aerospace, and industrial automation applications where durability, precision, and compliance are paramount.

Specification Summary & Compliance

This shoulder screw adheres to UNC thread standards with a Class 2A thread fit for consistent dimensional accuracy. The shoulder diameter tolerance is -0.004" to -0.002", and shoulder length tolerance is -0.005" to 0.005", ensuring precise manufacturing. It is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, confirming its suitability for environmentally conscious and regulated industrial use.