S-90276A557 1/4"-28 x 1/2" ASME B18.6.3 Steel Round Head Slotted Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with zinc-plated steel construction, extending service life in demanding industrial environments
• Precise Class 2A thread fit ensures smooth installation and reliable engagement with mating components
• High tensile strength (60,000 psi) provides exceptional load-bearing capacity for heavy-duty applications
• Fine UNF threading delivers enhanced vibration resistance and superior clamping force retention
• Rockwell B69 hardness rating maintains thread integrity and prevents stripping during repeated use
• Fully threaded design maximizes grip length and distributes stress evenly across the entire fastener
• Standard slotted drive offers compatibility with common hand tools for straightforward installation

Professional Applications & Engineering Value

Engineered for precision assemblies requiring reliable fastening solutions, these zinc-plated steel screws with 1/4"-28 UNF fine threading excel in applications where vibration resistance and consistent clamping force are critical. The rounded head profile and slotted drive style provide secure installation in machinery, electrical enclosures, and automotive components. The combination of 60,000 psi tensile strength and Rockwell B69 hardness ensures these fasteners maintain structural integrity under dynamic loads, while the Class 2A thread fit guarantees precise mating with corresponding UNF nuts and threaded holes. Ideal for maintenance, repair, and OEM applications across industrial sectors.

Specification Summary & Compliance

Manufactured to ASME B18.6.3 specifications with Class 2A thread fit tolerance and UNF fine thread spacing. Features include 0.472" head diameter, 1/2" length, and fully threaded right-hand design. Compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations, ensuring safe use in regulated industries.