S-90519A839 M20 ASTM A108, DIN 439B, ISO 4035 Hex Nuts

Key Features & Benefits at a Glance

• Enhanced corrosion resistance with black-oxide steel coating, ideal for humid or chemically aggressive environments
• Precise thread engagement with Class 6H thread fit and extra fine 1.5 mm pitch for secure, vibration-resistant connections
• Left-hand threading provides reliable performance in specialized applications where reverse rotation is required
• Space-saving thin profile (10 mm height) allows installation in confined areas without compromising strength
• Consistent quality assurance through compliance with ASTM A108, DIN 439B, and ISO 4035 manufacturing standards
• Environmental regulation compliance with RoHS 3 and REACH standards for global supply chain compatibility
• Class 04 strength rating ensures dependable performance in medium-duty mechanical assemblies

Professional Applications & Engineering Value

This M20 left hand hex nut with extra fine threading (1.5 mm pitch) addresses critical engineering challenges in specialized machinery and precision equipment. The black-oxide steel construction provides superior corrosion protection for applications exposed to moisture, chemicals, or outdoor elements, significantly extending service life in industrial environments. The thin profile design (DIN 439B specification) enables installation in space-constrained assemblies where standard nuts cannot fit, while maintaining full Class 04 strength performance. The left-hand metric thread configuration prevents accidental loosening in rotating systems that operate counterclockwise, making it essential for specific drive systems, conveyor mechanisms, and specialized manufacturing equipment where reverse-thread security is paramount.

Specification Summary & Compliance

This metric hex nut features M20x1.5 mm extra fine thread with Class 6H thread fit tolerance and left-hand thread direction. Manufactured to ASTM A108 material standards with dimensional compliance to DIN 439B (thin profile) and ISO 4035 specifications. The nut measures 30 mm across flats with 10 mm height and carries Class 04 strength rating. Fully compliant with RoHS 3 (2015/863/EU) with exemption 6(a) for lead as steel alloying element and REACH (EC 1907/2006) regulations current as of January 17, 2023.