S-91306A280 1/4"-20 x 1 1/4" ASTM F835 Steel Button Head Hex-Drive Screws

Key Features & Benefits at a Glance

• Exceptional durability with zinc-plated alloy steel construction that resists corrosion in demanding industrial environments
• Superior load-bearing capacity thanks to 120,000 PSI tensile strength and Rockwell C39 hardness for reliable performance under stress
• Precise thread engagement with Class 3A UNC coarse threads ensuring secure, vibration-resistant fastening in heavy machinery
• Easy installation and removal with 5/32" hex drive design providing superior torque transmission and tool accessibility
• Versatile rounded button head profile offering a low-profile finish while maintaining high clamping force distribution
• Full threading coverage along the 1-1/4" length for maximum grip and holding power across the entire fastener
• Regulatory compliance assurance meeting ASME, ASTM, RoHS 3, and REACH standards for quality and environmental safety

Professional Applications & Engineering Value

These zinc-plated alloy steel button head screws deliver critical performance advantages in industrial settings where vibration resistance and structural integrity are paramount. The fully threaded UNC coarse thread design prevents loosening under dynamic loads, making them ideal for machinery assembly, automotive components, and heavy equipment manufacturing. The Class 3A thread fit ensures precise tolerance matching with mating components, eliminating play while facilitating easier assembly. The zinc plating provides essential corrosion protection in environments exposed to moisture and chemicals, while the rounded button head profile offers a flush mounting solution where clearance is limited. These high-strength fasteners solve common engineering challenges of joint failure, corrosion-induced degradation, and maintenance accessibility in demanding applications.

Specification Summary & Compliance

This 1/4"-20 x 1-1/4" button head screw features precision UNC coarse threads with Class 3A fit for superior dimensional accuracy and engagement. Manufactured to exacting ASME B18.3 and ASTM F835 specifications, these fasteners guarantee consistent performance and interchangeability. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations, ensuring safe use across global markets. With fully threaded design and standardized 5/32" hex drive, these screws provide reliable fastening solutions for professional industrial applications requiring certified quality assurance.