S-91099A155 4-40 x 1/4" ASME B18.6.3 Stainless Steel Phillips Flat Head Screws
Stainless Steel Phillips Flat Head Screws
Image may differ from product. See technical specification for details.
Basic Information
Head Parameters
Dimensions
Thread Parameters
Tip & Drive Parameters
Material & Strength
Temperature & Environment
- Fast delivery
- Enjoy discounts on bulk purchases
- Secure Payment
- Fast Global Shipping
Key Features & Benefits at a Glance
- Superior corrosion resistance with passivated 18-8 stainless steel construction, ideal for harsh industrial environments
- Exceptional 80,000 PSI tensile strength ensures reliable fastening under high-stress conditions
- Precise Class 2A thread fit provides smooth installation and consistent engagement in UNC coarse threaded applications
- Undercut flat head design with 82° countersink angle enables flush mounting for clean, professional finishes
- Phillips drive compatibility (No. 1 size) offers widespread tool accessibility and efficient installation
- Full threading along 1/4" length maximizes grip strength and distribution across the entire fastener
- Comprehensive regulatory compliance including ASME B18.6.3, RoHS 3, and REACH for global industrial acceptance
Professional Applications & Engineering Value
These 4-40 UNC flat head screws deliver critical engineering solutions where flush surface mounting and corrosion resistance are paramount. The passivated 18-8 stainless steel construction prevents galvanic corrosion and withstands demanding environments, while the undercut flat head profile ensures secure seating without protrusion in precision assemblies. The coarse UNC threading provides excellent holding power in softer materials and faster installation times. These Phillips drive machine screws are engineered for applications requiring reliable 80,000 PSI tensile strength in electronics enclosures, machinery panels, and automotive components where vibration resistance and regulatory compliance are essential.
Specification Summary & Compliance
Manufactured to precise Class 2A thread fit tolerances with UNC coarse threading (4-40 size) and 1/4" length. Fully compliant with ASME B18.6.3 manufacturing specifications, RoHS 3 (2015/863/EU) environmental directives, and REACH (EC 1907/2006) chemical safety regulations. Features 82° countersink angle and Rockwell B80 hardness for consistent performance in industrial fastening applications.
