S-90298A169 1/4"-20 ASME B18.3 Shoulder Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with 18-8 stainless steel construction and passivated finish, ideal for harsh industrial environments
• Precise alignment and spacing ensured by the shoulder design with tight diameter tolerance of -0.001" to 0.001"
• High-strength threading with Class 3A fit for secure, vibration-resistant fastening in demanding applications
• Easy installation and removal using the 5/32" hex drive socket head with knurled texture for improved grip
• Reliable performance in automated assembly due to consistent UNC coarse thread and right-hand direction
• Compliance with industry standards including ASME B18.3, ensuring dimensional accuracy and interchangeability
• Environmentally responsible manufacturing with RoHS 3 and REACH compliance for safe use in regulated industries

Professional Applications & Engineering Value

This 1/4"-20 UNC thread shoulder screw delivers exceptional engineering value in precision machinery, automation systems, and fixturing applications where exact component alignment is critical. The 18-8 stainless steel material with passivated finish provides excellent corrosion resistance, extending service life in humid or chemically aggressive environments. The Class 3A thread fit ensures minimal backlash and superior vibration resistance, while the knurled socket head with hex drive enables quick tool engagement and high torque application without slippage. The precisely machined shoulder acts as both a pivot point and spacer, eliminating the need for additional washers or bushings in assemblies requiring rotational movement or precise axial positioning.

Specification Summary & Compliance

This shoulder screw maintains Class 3A thread fit with UNC coarse threading (1/4"-20) and right-hand direction. Shoulder dimensions include 5/16" diameter with -0.001" to 0.001" tolerance and 1/8" length with -0.005" to 0.005" tolerance. Manufactured to ASME B18.3 specifications for dimensional consistency and certified RoHS 3 (2015/863/EU) Compliant and REACH (EC 1907/2006) Compliant for environmental safety standards.