S-91082A138 ASTM A108, ASTM B633 Inch-to-Metric Female Hex Thread Adapters

Key Features & Benefits at a Glance

• Seamless Inch-to-Metric Conversion – Enables reliable connection between 8-32 (inch) and M8 (metric) threaded components, eliminating compatibility issues in mixed-standard environments.
• Exceptional Durability – Made from zinc-plated steel with Rockwell B85 hardness, offering superior resistance to wear, corrosion, and mechanical stress in demanding applications.
• High Tensile Strength – Withstands up to 78,000 psi tensile strength, ensuring secure, long-lasting connections under heavy loads without failure.
• Easy Installation & Removal – Features a 1/2" external hex drive and 2 1/2" hex length for straightforward tool engagement and torque application.
• Precision Thread Fit – Class 2B (inch) and Class 6H (metric) thread fits guarantee accurate alignment and vibration resistance, reducing the risk of cross-threading.
• Compliance with Industry Standards – Meets ASTM A108 and ASTM B633 specifications, ensuring consistent quality and performance in industrial settings.
• Environmental & Safety Compliance – RoHS 3 compliant with exemption for lead as an alloying element, supporting safe and sustainable usage.

Professional Applications & Engineering Value

This female hex thread adapter is engineered to solve critical challenges in industrial and mechanical systems where inch-to-metric thread adaptation is required. The zinc-plated steel construction provides excellent corrosion resistance, extending service life in harsh environments like manufacturing plants, automotive assembly, and heavy machinery. Its external hex drive design allows for easy integration with standard tools, reducing installation time and minimizing downtime. By ensuring precise thread fit (Class 2B and 6H), it prevents leaks and loosening under vibration, making it ideal for hydraulic systems, pneumatic equipment, and precision instrumentation. The adapter’s robust 78,000 psi tensile strength and compliance with ASTM standards deliver reliability that engineers and procurement specialists trust for mission-critical applications.

Specification Summary & Compliance

The adapter maintains high dimensional accuracy with Class 2B thread fit for inch (8-32) and Class 6H for metric (M8 x 1.25 mm), adhering to standardized tolerances for consistent performance. It is manufactured in compliance with ASTM A108 and ASTM B633 specifications, covering material quality and plating requirements. Additionally, the product is RoHS 3 (2015/863/EU) compliant with exemption 6(a)-I for lead as an alloying element in steel, ensuring it meets environmental and safety regulations for global industrial use.