S-90519A821 M18 ASTM A108, DIN 439B, ISO 4035 Hex Nuts

Key Features & Benefits at a Glance

• Left-hand threading provides secure fastening in applications requiring reverse-thread safety and prevents loosening under counter-clockwise rotation.
• Black-oxide steel construction offers enhanced corrosion resistance and durability in demanding industrial environments.
• Thin profile design (9mm height) saves space and weight, ideal for compact assemblies without compromising strength.
• Class 04 strength rating ensures reliable performance under moderate stress, suitable for general-purpose mechanical applications.
• Class 6H thread fit guarantees precise engagement with mating bolts, reducing the risk of cross-threading and improving assembly efficiency.
• Coarse 2.5 mm pitch allows for quicker installation and removal, minimizing assembly time in high-volume operations.
• Compliance with RoHS 3 and REACH ensures environmental safety and regulatory adherence for global supply chain integration.

Professional Applications & Engineering Value

This M18 left-hand thread hex nut is engineered to address critical challenges in machinery and equipment where standard right-hand threads may unscrew due to vibrational or rotational forces. The black-oxide steel material provides a protective layer against rust and wear, extending service life in humid or abrasive conditions. Its thin profile is particularly valuable in confined spaces, such as automotive components, conveyor systems, and electrical enclosures, where every millimeter counts. The coarse metric thread with 2.5 mm pitch ensures rapid fastening, reducing labor costs in assembly lines. By meeting ASTM A108, DIN 439B, and ISO 4035 standards, it delivers consistent quality and interchangeability, minimizing downtime and maintenance issues in industrial settings.

Specification Summary & Compliance

This hex nut features a Class 6H thread fit per ISO standards, ensuring dimensional accuracy and reliable performance. It complies with ASTM A108, DIN 439B, and ISO 4035 manufacturing specifications, guaranteeing uniformity in metric coarse threading (M18 x 2.5 mm). The product is RoHS 3 (2015/863/EU) compliant with exemption 6(a) for lead as an alloying element in steel and REACH (EC 1907/2006) compliant as of January 17, 2023, supporting sustainable and safe industrial practices.