Value Collection 1.1421FS 1/4-20x1 Flat Head Spanner Screw

Product Description

The VALUE COLLECTION 1.1421FS is a 1/4-20 x 1 inch flat head spanner machine screw manufactured from grade 18-8 stainless steel with a bright, uncoated finish. It features a UNC (Unified National Coarse) thread form and an overall length of 1 inch. The flat head profile sits flush with or below the surface of the mating material when properly countersunk, making it well suited for applications where a low-profile fastener is required. The spanner drive resists unauthorized removal, a common requirement in tamper-resistant assemblies. Fabricators, millwrights, and maintenance technicians install these fasteners across a range of light industrial and commercial applications.

This screw is appropriate for use in light-duty mechanical assemblies, panel and enclosure work, and tamper-resistant installations in both indoor and outdoor environments. Grade 18-8 stainless steel provides moderate corrosion resistance suitable for general-purpose service where mild moisture or chemical exposure is a concern. The inch-system, 1/4-20 UNC thread mates with standard tapped holes or hex nuts of the same designation.

Key Features

• 1/4-20 UNC thread for compatibility with standard inch-system tapped holes and hardware
• Flat head design seats flush when installed in a properly sized countersink
• Spanner drive provides tamper resistance in security-sensitive installations
• Grade 18-8 stainless steel construction offers corrosion resistance for indoor and light outdoor use
• Bright, uncoated finish — no added plating that could affect thread fit or dimensional tolerances
• Overall length and length under head both measure 1 inch

Compatibility

Designed for use in standard 1/4-20 UNC tapped holes and compatible with inch-system spanner drive tools. No washer is included or required by this fastener style.

Installation Notes

Installation requires a spanner drive bit or key sized to the fastener head. Ensure the mating hole is tapped to 1/4-20 UNC specification and that the countersink angle matches the flat head profile before driving the screw to avoid galling the stainless steel threads. Apply thread lubricant or anti-seize compound when torquing stainless fasteners into stainless tapped holes to reduce the risk of galling and seizing. Follow applicable mechanical or structural codes for fastener preload requirements in the specific assembly.