S-99553A148 4-40 x 1/4" ASME B18.3 Set Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance in harsh environments due to 316 stainless steel construction
• Precise and secure component positioning with Class 3A thread fit for minimal play and vibration resistance
• Excellent torque transmission and strip resistance from the 0.050" hex drive and Rockwell B80 hardness
• Reliable, non-slip fastening provided by the oval tip design for concentrated holding force
• Easy and quick installation with right-hand coarse (UNC) threads in common industrial applications
• Space-saving headless design ideal for applications where protruding fastener heads are not permissible
• Long-term operational integrity ensured by compliance with ASME B18.3, RoHS 3, and REACH standards

Professional Applications & Engineering Value

This 4-40 UNC Class 3A 316 Stainless Steel Set Screw is engineered to address critical challenges in precision assembly and machinery. The headless design and oval tip provide a flush finish and concentrated point contact, preventing component slippage in high-vibration systems like motor shafts, gears, and pulleys. Manufactured from 316 stainless steel, it offers exceptional resistance to chlorides and acidic conditions, making it ideal for marine, chemical processing, and food-grade equipment. The coarse thread spacing and Class 3A fit ensure rapid installation and a tight, reliable clamp in industrial set screw applications, reducing maintenance cycles and enhancing machine uptime.

Specification Summary & Compliance

This set screw features a 4-40 UNC thread with a precision Class 3A fit, ensuring dimensional accuracy and interchangeability. It is manufactured in accordance with the ASME B18.3 standard and is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, confirming its suitability for use in regulated and environmentally conscious industries.