S-91478A558 Length 4" ASME B18.2.1 Wood Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with zinc-plated steel construction for long-lasting performance in demanding wood applications
• Enhanced driving efficiency with external hex head design providing maximum torque transfer and reduced cam-out
• Exceptional holding power through thread forming technology that creates stronger, more secure connections in wood materials
• Optimized thread engagement with 10 threads per inch and partial threading for controlled penetration and reduced splitting
• Reliable dimensional consistency meeting ASME B18.2.1 specifications for precise fit and predictable performance
• Environmental compliance assurance with RoHS 3 and REACH compliance for safe, sustainable manufacturing standards
• Versatile 4" length with 2½" minimum thread length providing deep penetration for heavy-duty wood fastening applications

Professional Applications & Engineering Value

These zinc-plated steel wood screws deliver exceptional engineering value through their thread forming design that eliminates the need for pre-drilling in many wood applications. The external hex drive system ensures maximum torque application without stripping, while the partial threading provides controlled clamping force and reduces material splitting. The 1/4" diameter combined with 4" length makes these wood screws ideal for structural applications, furniture manufacturing, and construction projects requiring reliable, long-term fastening solutions. The right-hand thread direction with 10 threads per inch offers optimal balance between installation speed and holding strength in various wood densities.

Specification Summary & Compliance

Manufactured to ASME B18.2.1 standards with inch system measurements, these screws feature precise dimensional control including 0.25" thread diameter, 0.438" head width, and 0.172" head height. The thread forming tapping method ensures consistent performance while meeting comprehensive regulatory requirements including RoHS 3 (2015/863/EU) compliance and REACH (EC 1907/2006) compliance. The pointed tip and round shank cross-section facilitate easy starting and straight driving in wood substrates.