S-92620A277 1 1/4"-12 x 4" ASME B18.2.1, SAE J429 High-Strength Grade 8 Steel Hex Head Screws

Key Features & Benefits at a Glance

• Exceptional strength for demanding applications with Grade 8 rating and 150,000 psi tensile strength, ensuring reliable performance under high stress.
• Superior corrosion resistance provided by the zinc yellow-chromate plating, extending service life in harsh industrial environments.
• Precise and secure fastening due to the UNF fine thread and Class 2A thread fit, minimizing the risk of loosening in critical assemblies.
• High durability and wear resistance from Rockwell C33 hardness, reducing maintenance needs and replacement frequency.
• Easy installation and removal with the external hex drive and hex head design, allowing for efficient use with standard tools.
• Optimized for heavy-duty use with a partially threaded shank, providing strong grip where needed without unnecessary threading.
• Compliance with industry standards including ASME B18.2.1, RoHS 3, and REACH, ensuring safety and environmental responsibility.

Professional Applications & Engineering Value

This Grade 8 hex head screw is engineered for heavy-duty industrial applications where failure is not an option. The steel material combined with zinc yellow-chromate plating offers excellent protection against corrosion, making it ideal for outdoor machinery, construction equipment, and automotive assemblies exposed to moisture and chemicals. The 1 1/4"-12 UNF fine thread and Class 2A thread fit ensure tight, vibration-resistant connections, reducing the need for frequent retightening in dynamic environments. With a partially threaded design, it provides focused clamping force, solving common issues of thread stripping in high-load scenarios. This screw delivers reliable performance in sectors like manufacturing, infrastructure, and transportation, where tensile strength and longevity are critical.

Specification Summary & Compliance

This fastener adheres to precise dimensional tolerances, including Class 2A thread fit for consistent engagement and UNF fine thread standards for secure fastening. It meets ASME B18.2.1 specifications, ensuring compatibility and reliability in mechanical systems. Additionally, it is RoHS 3 (2015/863/EU) Compliant and REACH (EC 1907/2006) Compliant, confirming adherence to environmental and safety regulations without hazardous substances.