Value Collection R88448642 4-40 X 1/4 Button Head Machine Screw

Product Description

The VALUE COLLECTION R88448642 is a 4-40 x 1/4 inch button head machine screw designed for precision fastening applications in mechanical assemblies, electrical enclosures, and equipment fabrication. Constructed from 18-8 stainless steel with a bright, uncoated finish, this screw offers solid corrosion resistance suitable for indoor and light outdoor use. The Pin-In Torx drive provides tamper-resistance and improved driver engagement compared to standard Torx profiles. Length is measured under the head. Thread standard is UNC (Unified National Coarse), sized at 4-40. This fastener is handled and installed by millwrights, electricians, mechanical technicians, and equipment assemblers working across light-duty industrial and commercial settings.

This screw is suited for applications requiring a low-profile button head with secure torque transfer, including panel mounting, electronic chassis assembly, light structural bracketing, and general-purpose machine fastening. The 4-40 thread size is commonly found in instrumentation, control panels, HVAC equipment covers, and electrical device assemblies where small-diameter fasteners are specified. The minimum order quantity is 25 pieces per order, with each package containing 1 unit.

Key Features

• 18-8 stainless steel construction provides corrosion resistance and durability in light-duty environments
• Button head profile delivers a low-profile, finished appearance suitable for visible panel applications
• Pin-In Torx drive adds tamper resistance and reduces cam-out during installation
• 4-40 UNC thread standard ensures compatibility with standard tapped holes and nuts of the same designation
• Bright, uncoated finish maintains dimensional accuracy and avoids coating buildup in tight tolerances
• Length measured under head at 1/4 inch for precise fit in shallow or through-hole applications

Compatibility

Designed as a standard 4-40 UNC machine screw for use in any tapped hole or threaded insert conforming to the 4-40 Unified National Coarse thread standard.

Installation Notes

Installation is performed by mechanical technicians or assemblers using a Pin-In Torx bit of the appropriate size. Verify that the mating tapped hole or nut is 4-40 UNC before driving the screw to avoid cross-threading. Do not exceed the rated torque range for 18-8 stainless steel fasteners of this diameter, as overtightening can cause galling or thread failure. Ensure the fastener length under head is appropriate for the material stack-up to achieve full thread engagement.