S-90044A131 1/4"-20 x 4" ASTM A574 Alloy Steel Socket Head Screws

Key Features & Benefits at a Glance

• Exceptional Tensile Strength – With 170,000 psi tensile strength, this screw provides superior load-bearing capacity and resistance to failure in demanding applications.
• Enhanced Corrosion Resistance – The black-oxide finish on alloy steel offers improved protection against rust and environmental degradation, extending service life.
• Precise Thread Fit – Class 3A UNC coarse threads ensure tight, reliable fastening with reduced risk of cross-threading and improved assembly accuracy.
• High Hardness & Durability – Rockwell C37 hardness provides excellent wear resistance and maintains structural integrity under high-stress conditions.
• Standard Socket Head Design – The hex drive (3/16") and standard socket head profile allow for easy installation and removal with common tools, minimizing assembly time.
• Full Thread Engagement – Fully threaded design offers consistent clamping force along the entire 4" length, ideal for deep or adjustable fastening needs.
• Regulatory Compliance – Meets ASTM A574, RoHS 3, and REACH standards, ensuring material safety and suitability for global industrial markets.

Professional Applications & Engineering Value

This black-oxide alloy steel socket head cap screw is engineered to address critical challenges in heavy machinery, automotive, and construction sectors where vibration, high loads, and corrosive environments are common. The UNC coarse thread with Class 3A fit ensures rapid, secure fastening even in materials prone to stripping, while the 170,000 psi tensile strength and Rockwell C37 hardness prevent deformation under extreme operational stress. The black-oxide surface treatment adds a layer of corrosion resistance without compromising dimensional accuracy, making these screws ideal for assembly lines, equipment frames, and structural supports that demand long-term reliability and minimal maintenance. Their fully threaded design accommodates variable material thicknesses, offering flexibility in complex engineering setups.

Specification Summary & Compliance

This socket head cap screw features a 1/4"-20 UNC coarse thread with Class 3A precision fit, ensuring tight tolerances and reliable performance in high-vibration environments. Manufactured in compliance with ASTM A574 specifications for alloy steel socket head cap screws, it also meets RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulatory requirements, confirming its suitability for use in environmentally conscious and international industrial applications.