S-91870A766 1/4"-20 x 3/8" ASME B18.3 Tamper-Resistant Torx Steel Flat Head Screws
Tamper-Resistant Torx Steel Flat Head Screws
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Basic Information
Head Parameters
Dimensions
Thread Parameters
Tip & Drive Parameters
Material & Strength
Temperature & Environment
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Key Features & Benefits at a Glance
- Enhanced tamper resistance with T27 Torx drive design to prevent unauthorized access in secure applications
- Superior corrosion protection through black oxide finish, extending service life in harsh industrial environments
- Exceptional mechanical strength with 160,000 psi tensile strength and Rockwell C38 hardness for heavy-duty applications
- Precision thread engagement with Class 2A UNC coarse threads ensuring reliable fastening and vibration resistance
- Optimized flush mounting featuring undercut flat head design for seamless surface integration
- Full thread coverage across the entire 3/8" length for maximum grip and load distribution
- Regulatory compliance assurance meeting both industry standards and environmental regulations
Professional Applications & Engineering Value
These 1/4-20 UNC alloy steel flat head screws with tamper-resistant T27 drive address critical security and reliability challenges in industrial settings. The black oxide finish provides essential corrosion resistance for machinery, electrical enclosures, and outdoor equipment where environmental exposure is a concern. The undercut flat head profile ensures flush installation without protrusion, preventing snagging while maintaining aesthetic requirements. Engineered with fully threaded coarse UNC patterns, these screws deliver superior holding power in metal assemblies, plastic components, and structural frameworks where vibration resistance is paramount. The combination of 160,000 psi tensile strength and specialized drive system makes them ideal for permanent installations in public infrastructure, transportation equipment, and high-security facilities where maintenance access must be controlled.
Specification Summary & Compliance
These flat head screws feature precision Class 2A thread fit with 1/4"-20 UNC coarse threading and 82° countersink angle per ASME B18.3 specifications. Manufacturing compliance includes RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental standards, ensuring safe use across regulated industries. The mechanical properties guarantee consistent performance with Rockwell C38 hardness and verified dimensional accuracy throughout production batches.
