S-95345A023 4-40 x 1/4" ASME B18.13 Stainless Steel Pan Head Phillips Screws with Internal-Tooth Lock Washer

Key Features & Benefits at a Glance

• Superior corrosion resistance with 18-8 stainless steel construction and passivated finish for extended service life in harsh environments
• Reliable vibration resistance through integrated 410 stainless steel internal-tooth lock washer that maintains secure fastening under dynamic loads
• High-strength performance with 70,000 psi tensile strength ensuring durability in demanding industrial applications
• Quick installation and removal with Phillips No. 1 drive style providing efficient assembly while minimizing tool slippage
• Precise thread engagement through UNC coarse threads and Class 2A fit enabling consistent performance and easy alignment
• Versatile pan head design offering excellent bearing surface and streamlined profile for various assembly requirements
• Full thread coverage along the entire 1/4" length maximizing grip strength and load distribution

Professional Applications & Engineering Value

These 4-40 UNC coarse thread screws with internal-tooth lock washers deliver critical vibration resistance in machinery, electronics, and precision equipment where loosening under dynamic loads poses significant reliability concerns. The 18-8 stainless steel core with passivated finish provides exceptional corrosion protection in manufacturing environments exposed to moisture, chemicals, or temperature variations. The combination of fully threaded design and Class 2A thread fit ensures consistent clamping force distribution while the 410 stainless steel washer maintains permanent tension, eliminating the need for secondary locking mechanisms. This engineered solution addresses common failure points in assembly operations, reducing maintenance frequency and improving overall equipment uptime.

Specification Summary & Compliance

Manufactured to exacting ASME B18.13 specifications with UNC coarse threads in Class 2A tolerance for precision fit. The complete assembly meets RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) compliance standards, ensuring environmental responsibility and workplace safety. Components include 18-8 stainless steel screw body with passivated finish and 410 stainless steel internal-tooth lock washer, delivering 70,000 psi tensile strength for industrial-grade performance.