S-90271A578 5/16"-18 x 1/2" ASME B18.6.3 Steel Truss Head Slotted Screws

Key Features & Benefits at a Glance

• Enhanced corrosion resistance with zinc-plated steel construction for long-lasting performance in demanding environments
• Superior load distribution thanks to the wide truss head design, minimizing surface damage and pull-through
• Reliable fastening strength with a high 60,000 psi tensile strength and Rockwell B69 hardness for heavy-duty applications
• Easy installation and removal with a standard slotted drive and fully threaded coarse UNC design
• Precise thread fit with Class 2A tolerance ensuring consistent engagement and vibration resistance
• Broad industrial compliance meeting ASME B18.6.3 standards, RoHS 3, and REACH for global regulatory acceptance
• Optimized for high-torque applications due to the rounded truss head profile and right-hand thread direction

Professional Applications & Engineering Value

Engineered for industrial and construction settings, these zinc-plated steel slotted truss head screws address critical fastening challenges where vibration resistance and surface preservation are paramount. The wide truss head distributes clamping force over a larger area, preventing damage to softer materials and reducing the risk of loosening under dynamic loads. With coarse UNC threading and a Class 2A fit, they provide quick assembly and reliable hold in wood, metal, and plastic components, making them ideal for machinery, electrical enclosures, and structural assemblies. The zinc plating offers a protective barrier against rust and corrosion, extending service life in humid or outdoor environments, while the slotted drive ensures compatibility with standard tools for maintenance and field repairs.

Specification Summary & Compliance

This screw features precise UNC coarse threads with a Class 2A thread fit for consistent dimensional accuracy and reliable performance. It is manufactured in compliance with ASME B18.6.3 specifications, ensuring adherence to industrial standards for head and thread geometry. The product is also RoHS 3 (2015/863/EU) Compliant and REACH (EC 1907/2006) Compliant, confirming it meets environmental and safety regulations for hazardous substances, making it suitable for use in regulated markets and sustainable manufacturing processes.