S-90058A538 1/4"-20 x 1/2" Tamper-Resistant Tri-Groove-Drive Steel Round Head Screws

Key Features & Benefits at a Glance

• Exceptional corrosion resistance through zinc-plated steel construction for extended service life in harsh industrial environments
• Superior torque transmission and reduced cam-out with Tri-Groove drive design ensuring reliable installation and removal
• Precise thread engagement and vibration resistance achieved through Class 3A thread fit with UNC coarse spacing
• High-load bearing capability with 80,000 PSI tensile strength for demanding mechanical applications
• Enhanced durability and wear resistance from Rockwell C28 hardness maintaining performance under stress
• Maximum grip and holding power through fully threaded design along the entire 1/2" length
• Optimized head profile with 3/8" diameter rounded head providing smooth finish and reduced snagging

Professional Applications & Engineering Value

Engineered for industrial assembly and heavy-duty equipment, these zinc-plated steel screws deliver critical performance where reliability matters most. The Tri-Groove drive system eliminates common installation issues like cam-out, while the Class 3A UNC threads with coarse spacing ensure rapid assembly and superior vibration resistance in machinery, automotive, and construction applications. The combination of 80,000 PSI tensile strength and Rockwell C28 hardness provides exceptional resistance to mechanical stress, making these rounded head fasteners ideal for applications requiring both structural integrity and corrosion protection from the zinc plating.

Specification Summary & Compliance

Manufactured to precise dimensional standards with UNC thread form, Class 3A thread fit, and coarse thread spacing. The 1/4"-20 thread size and 1/2" length maintain strict tolerance control. Complies with industry standards for inch system fasteners and meets material specifications for zinc-plated steel components suitable for industrial use.