S-90585A044 1/4"-20 x 2 3/4" ASME B18.3 Stainless Steel Hex Drive Flat Head Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance in harsh environments thanks to 316 stainless steel construction and passivated finish.
• Exceptional holding power and reliability ensured by the Class 3A thread fit and 70,000 psi tensile strength.
• Optimized for high-strength applications with a Rockwell B55 hardness for excellent durability and wear resistance.
• Easy and secure installation with a standard 82° countersink angle for a flush fit and a 5/32" hex drive for positive torque transmission.
• Maximum grip and fastening efficiency provided by the fully threaded 1/4"-20 UNC coarse spacing design.
• Guaranteed dimensional consistency and interchangeability by conforming to the rigorous ASME B18.3 standard.
• Safe for regulated industries with full compliance to RoHS 3 and REACH environmental regulations.

Professional Applications & Engineering Value

This 1/4"-20 UNC Flat Head Screw is engineered to solve critical fastening challenges in demanding sectors. Manufactured from 316 Stainless Steel and featuring a passivated finish, it delivers outstanding resistance to chemicals, saltwater, and other corrosive agents, making it an ideal choice for marine, chemical processing, and industrial applications. The fully threaded body with coarse UNC spacing and precise Class 3A fit ensures rapid assembly and superior vibration resistance, preventing loosening under dynamic loads. The flat head with an 82° countersink provides a clean, flush finish, while the internal hex drive allows for high-torque installation. This combination of material properties and mechanical design offers a reliable, long-lasting fastening solution that reduces maintenance downtime and enhances structural integrity.

Specification Summary & Compliance

This fastener adheres to strict dimensional and quality standards, including a Class 3A thread fit for high precision and a head diameter tolerance of -0.051" to 0". It is manufactured in accordance with the ASME B18.3 specification for socket cap screws. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring it is free from hazardous substances and safe for use in environmentally sensitive and regulated industries.