S-98892A113 1/4"-28 NAS1291C4M Flange Nuts

Key Features & Benefits at a Glance

• Superior vibration resistance with center lock distorted threads that maintain secure fastening under extreme conditions
• Exceptional durability provided by A286 stainless steel construction, offering high strength and corrosion resistance
• Precise thread engagement with Class 3B fit ensuring reliable, tight connections in critical assemblies
• Integrated flange design eliminates need for separate washers, speeding up installation and reducing part count
• Easy installation with included lubricant and standard external hex drive for straightforward tool compatibility
• Compliance with NAS1291C4M specifications guarantees consistent performance in aerospace and industrial applications
• Environmental compliance with REACH and RoHS 3 standards for safe use in regulated industries

Professional Applications & Engineering Value

This A286 stainless steel flange lock nut delivers critical vibration resistance in demanding environments through its center lock distorted thread design, which prevents loosening under dynamic loads. The 1/4"-28 UNF fine thread configuration ensures superior clamping force distribution, while the integrated 0.42" flange provides enhanced bearing surface area, reducing stress concentration on joined materials. Ideal for aerospace assemblies, heavy machinery, and transportation equipment where NAS1291C4M compliance is mandatory, this nut maintains integrity in high-temperature and corrosive conditions thanks to its premium material composition and Class 3B thread fit precision.

Specification Summary & Compliance

Manufactured to NAS1291C4M standards with Class 3B thread fit for precise engagement in UNF fine threads (1/4"-28). Features include right-hand thread direction, external hex drive (5/16" width), and dimensions of 0.42" flange diameter with 7/32" height. Compliant with REACH (EC 1907/2006) and RoHS 3 (2015/863/EU) environmental regulations, ensuring safe usage across industrial sectors.