S-99355A320 1/4"-20 x 1 1/2" ASME B18.3 Tamper-Resistant Asymmetrical-Drive Stainless Steel Button Head Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with 18-8 stainless steel construction, ideal for harsh environments and long-term reliability
• High tensile strength of 70,000 psi ensures secure, vibration-resistant fastening in demanding applications
• Class 2A thread fit provides consistent, reliable engagement with standard nuts and tapped holes
• ASME B18.3 compliance guarantees dimensional accuracy and interchangeability with other standard components
• RoHS 3 and REACH compliance meets international environmental regulations for safe industrial use
• Fully threaded design offers maximum grip length and adjustment flexibility throughout the entire shank
• Rockwell B70 hardness maintains thread integrity and prevents stripping during installation

Professional Applications & Engineering Value

Engineered for industrial assemblies requiring both corrosion resistance and mechanical strength, these 18-8 stainless steel rounded head screws solve critical fastening challenges in machinery, electrical enclosures, and structural frameworks. The 1/4"-20 UNC coarse threading enables quick installation and superior resistance to vibration loosening, while the button head profile provides a low-profile, aesthetically clean finish. With fully threaded construction and Class 2A thread fit, these fasteners deliver consistent clamping force across diverse material thicknesses, reducing assembly time and minimizing the risk of joint failure in high-stress environments.

Specification Summary & Compliance

This fastener maintains Class 2A thread fit tolerance per UNC standards with 1/4"-20 coarse thread spacing and 1-1/2" length. Manufacturing conforms to ASME B18.3 specifications for dimensional consistency. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations, ensuring safe usage across global industrial markets.