S-91385A619 3/8"-16 x 1/2" ASME B18.3, ASTM F912 Set Screws

Key Features & Benefits at a Glance

• Permanent vibration resistance with integrated Nylon Patch thread locker, preventing loosening under dynamic loads
• Enhanced corrosion protection from Black-Oxide surface treatment, extending service life in harsh environments
• Superior thread engagement with Class 3A fit UNC coarse threads, ensuring precise assembly and reduced cross-threading risk
• High-strength durability from Rockwell C45 hardened alloy steel, maintaining clamp force under extreme mechanical stress
• Wide temperature tolerance from -50°F to 250°F, guaranteeing reliable performance in fluctuating thermal conditions
• Secure tamper-resistant fastening with headless hex drive design, ideal for space-constrained applications
• Consistent cup tip contact providing concentrated surface pressure for superior grip on shafts and collars

Professional Applications & Engineering Value

Engineered for high-vibration industrial assemblies, this Black-Oxide Alloy Steel set screw solves critical loosening issues in machinery, automotive, and aerospace components. The permanent Nylon Patch thread locker chemically bonds with mating threads, creating a maintenance-free lock that outperforms mechanical washers. With UNC coarse threads and Class 3A precision fit, installation torque is consistently transferred without galling, while the cup tip design concentrates bearing pressure to prevent rotational slip in pulley systems, gears, and coupling joints. Its headless hex drive profile allows flush mounting in confined spaces where protruding fasteners would interfere with moving parts.

Specification Summary & Compliance

Manufactured to ASME B18.3 and ASTM F912 specifications with Class 3A thread fit for superior dimensional accuracy. Compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental standards. Features 3/8"-16 UNC coarse threads, 1/2" length, and 3/16" hex drive with right-hand thread direction.