S-91249A370 1/4"-28 x 1/2" ASME B18.6.3 Stainless Steel Pan Head Phillips Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with Black-Oxide coated 18-8 Stainless Steel for extended service life in harsh environments
• High tensile strength of 70,000 psi ensures reliable performance under heavy loads and vibration
• Rockwell B70 hardness provides excellent wear resistance and durability
• UNF fine threading delivers superior holding power and vibration resistance in precision applications
• Phillips No. 3 drive enables efficient installation with common tools while reducing cam-out risk
• Full compliance with ASME B18.6.3 standards guarantees dimensional accuracy and interchangeability
• RoHS 3 and REACH compliance ensures environmental responsibility and regulatory acceptance

Professional Applications & Engineering Value

These Black-Oxide 18-8 Stainless Steel Rounded Head Screws are engineered to solve critical industrial challenges where corrosion resistance and mechanical strength are paramount. The pan head design with Phillips No. 3 drive provides optimal clamping force distribution while facilitating quick assembly in tight spaces. The UNF fine threading (1/4"-28) ensures superior vibration resistance in machinery, automotive components, and electronic enclosures where loosening under dynamic loads is a concern. The Black-Oxide surface treatment on 18-8 stainless steel combines corrosion protection with reduced light reflection, making these screws ideal for outdoor equipment, marine applications, and industrial assemblies exposed to moisture and chemicals. The fully threaded design allows for maximum engagement depth, providing consistent clamping force throughout the entire fastener length.

Specification Summary & Compliance

This 1/4"-28 x 1/2" Rounded Head Screw features Class 2A thread fit for standard industrial applications, ensuring proper clearance and ease of assembly. Manufactured to exacting ASME B18.6.3 specifications for dimensional consistency and performance reliability. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations, meeting the latest standards for hazardous substance restrictions. The inch system measurement and standardized thread geometry ensure compatibility with existing industrial components and tooling.