S-94622A412 1/4"-28 x 21/32" AN4-5A Army-Navy Medium-Strength Steel Hex Head Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance from cadmium plating protects against harsh industrial environments, extending service life
• Precise Class 3A thread fit ensures reliable, vibration-resistant connections in critical assemblies
• High tensile strength of 120,000 psi provides exceptional load-bearing capacity for demanding applications
• Rockwell C26 hardness offers excellent durability and resistance to wear under repeated use
• External hex drive design allows for easy installation and removal with standard tools
• AN4-5A specification compliance guarantees consistent quality and interoperability in aerospace and defense applications
• Partially threaded shank enables secure clamping where unthreaded grip length is required

Professional Applications & Engineering Value

This 1/4"-28 UNF hex head screw delivers exceptional engineering value in applications requiring precision and reliability. The cadmium plated finish provides superior corrosion protection in challenging environments like marine, aerospace, and industrial equipment. With its Class 3A thread fit and fine thread spacing, this fastener maintains tight tolerances in vibration-prone assemblies, preventing loosening while ensuring consistent clamping force. The partially threaded design allows for optimal grip length control in structural applications, while the external hex drive facilitates quick installation in confined spaces. Manufactured from hardened steel with Rockwell C26 hardness, this screw withstands repeated stress cycles without compromising integrity, making it ideal for critical fastening applications where failure is not an option.

Specification Summary & Compliance

This inch system fastener features precise 1/4"-28 UNF threads with Class 3A fit tolerance for superior thread engagement. The screw meets AN4-5A specifications for dimensional accuracy and performance requirements. Manufacturing follows strict quality controls to ensure consistent thread diameter (0.25"), thread length (15/32"), and grip length (3/16") dimensions. The right-hand thread direction and fine thread spacing comply with UNF standards, while the cadmium plating process adheres to industry standards for corrosion protection.