S-90179A578 5/16"-18 x 1/2" Thumb Screws
Thumb Screws
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Basic Information
Head Parameters
Dimensions
Thread Parameters
Material & Strength
Temperature & Environment
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Key Features & Benefits at a Glance
- Effortless hand-tightening with a wide spade head and thumb-friendly design, eliminating the need for tools in quick assembly/disassembly scenarios.
- Enhanced grip and load distribution from the integrated flange, preventing the screw from pulling through softer materials and increasing joint stability.
- Superior durability and strength with a steel construction, Rockwell B55 hardness, and a high 40,000 psi tensile strength for reliable performance in demanding applications.
- Fast and easy coarse threading with UNC standard and Class 2A fit, enabling rapid installation and reducing cross-threading risks.
- Full-length threading provides maximum engagement and holding power along the entire 1/2" length of the screw.
- Confident material sourcing with full RoHS 3 compliance, ensuring the fastener meets stringent environmental and safety regulations.
- Versatile right-hand thread direction for standard clockwise tightening, compatible with a wide range of industrial components.
Professional Applications & Engineering Value
This steel thumb screw is engineered to solve critical challenges in maintenance panels, access doors, and machinery guards where tools are impractical. The flanged spade head design offers a substantial surface area for secure hand-tightening, while the flange acts as an integrated washer to protect surfaces and resist loosening under vibration. The 5/16"-18 UNC coarse thread and Class 2A fit ensure quick, reliable engagement, even in applications requiring frequent adjustment. Made from robust steel with a 40,000 psi tensile strength, it provides the durability needed for industrial environments, making it an ideal quick-release fastener for OEM equipment, electronics enclosures, and production jigs.
Specification Summary & Compliance
This thumb screw conforms to UNC thread standards with a Class 2A thread fit for consistent, reliable engagement. Key dimensional specifications include a 5/16"-18 thread size, a 1/2" length, and a 0.563" flange diameter. The product is manufactured to be fully RoHS 3 (2015/863/EU) Compliant, adhering to strict regulations on hazardous substances.
