S-91319A219 M8 ISO 7379 Shoulder Screws

Key Features & Benefits at a Glance

• Secure Vibration-Resistant Fastening: Integrated nylon pellet thread locker maintains clamp force from -50° to 250°F, preventing loosening in high-vibration industrial environments.
• Exceptional Strength & Durability: Manufactured from high-strength alloy steel with a Rockwell C32 hardness and 150,000 psi tensile strength for reliable performance under heavy loads.
• Precision Alignment & Pivot Function: The 25mm long, precision-ground shoulder with a tight diameter tolerance provides accurate component location and acts as a dependable bearing surface.
• Corrosion-Resistant & Professional Finish: The black oxide coating offers improved corrosion resistance and a clean, professional appearance for demanding applications.
• Easy Installation in Confined Spaces: The knurled hex socket head with a 5mm drive allows for high-torque installation and removal with standard tools, even in tight spaces.
• Guanteed Dimensional Consistency: The M8x1.25mm coarse thread with Class 5g6g fit ensures reliable, interchangeable assembly and compatibility with standard metric nuts.
• Globally Recognized Quality & Safety: Compliance with ISO 7379, RoHS 3, and REACH standards ensures product reliability and environmental safety for global supply chains.

Professional Applications & Engineering Value

This M8 shoulder screw is engineered to solve critical challenges in precision assembly. The alloy steel construction and black oxide finish provide the necessary strength and moderate corrosion resistance for machinery, automation systems, and jig and fixture manufacturing. The defining 25mm shoulder length acts as a precise shaft for locating gears, pulleys, and linkages, eliminating the need for separate bushings and reducing assembly complexity. The integrated nylon pellet thread locker is a key feature, ensuring the fastener remains securely in place despite constant vibration or thermal cycling, which is a common failure point in dynamic industrial equipment. This combination of precise shoulder fit, high tensile strength, and secure locking makes it an indispensable component for engineers seeking to enhance the reliability and longevity of their mechanical designs.

Specification Summary & Compliance

This shoulder screw features an M8x1.25mm coarse thread with a Class 5g6g thread fit per ISO standards, ensuring dimensional accuracy and interchangeability. The shoulder diameter is held to a tight tolerance of -0.049 to -0.01 mm, and the shoulder length tolerance is 0 to +0.25 mm. The product is manufactured in accordance with ISO 7379 and is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations.