S-92952A120 4-40 Shoulder Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with 18-8 stainless steel construction, ideal for harsh environments and frequent handling
• Precise alignment and secure positioning thanks to the 1/8" shoulder with tight tolerances for minimal play in assemblies
• Excellent hand-tightening grip provided by the knurled, raised round head, eliminating the need for tools in many applications
• High mechanical strength and durability with 70,000 psi tensile strength and Rockwell B83 hardness for reliable, long-term performance
• Wide compatibility and easy installation with the standard 4-40 UNC coarse thread and Class 2A fit for consistent engagement
• Flexible fastening options featuring both a thumb head for manual use and a 5/64" hex drive for tool-assisted tightening
• Compliance with environmental and safety standards, being RoHS 3 and REACH compliant for use in regulated industries

Professional Applications & Engineering Value

This 18-8 stainless steel thumb screw is engineered to address common challenges in precision assembly, such as misalignment and tool accessibility. The 1/8" shoulder diameter with precise fit ensures components are accurately positioned, reducing wear and improving operational reliability in mechanisms like optical devices, electronic enclosures, and calibration equipment. The combination of a knurled round head and hex drive offers versatility, allowing for quick hand adjustments or secure tool tightening in confined spaces. Its 4-40 UNC coarse thread with Class 2A fit provides consistent threading, while the stainless steel material delivers excellent corrosion resistance, making it suitable for industries like aerospace, medical devices, and laboratory instrumentation where durability and precision are critical.

Specification Summary & Compliance

This thumb screw adheres to UNC thread standards with a Class 2A thread fit for reliable dimensional accuracy. Key specifications include a thread size of 4-40, shoulder diameter of 1/8" with tolerance from -0.001" to 0", and shoulder length of 3/16" with tolerance from 0" to 0.002". It complies with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring it meets environmental and safety requirements for global use.