Buy Online 5/16-18 X 1-1/4″ Socket Cap Screws Flat Head Hex Socket Drive 18/8 Stainless Steel (100 / Pkg.)

Cap Screws Flat Socket 18/8 Stainless 5/16-18 X 1 1/4 are precision-engineered fasteners designed for durable, high-performance assembly in a wide range of applications. With a flat socket head and robust stainless construction, these screws offer a clean, low-profile look without compromising strength.

Made from 18/8 stainless steel (304 stainless), these cap screws deliver excellent corrosion resistance and long service life in both indoor and outdoor environments. The flat socket head provides a flush finish and reduces snag hazards in tight spaces, making them ideal for machinery, electronics enclosures, automotive projects, furniture assembly, and general DIY tasks.

Key Specifications

Material: 18/8 stainless steel (304) for superior corrosion resistance

Head style: Flat socket cap screw for a low-profile, flush appearance

Thread size: 5/16-18 UNC (coarse) for versatile fastening

Length: 1 1/4 in from under the head to end

Finish: Bright, durable stainless finish

Applications: Machinery, automotive, electronics enclosures, furniture, and DIY projects requiring a strong, corrosion-resistant fastener

Why Choose This Cap Screw?

Combining strength with corrosion resistance, 18/8 stainless cap screws are a reliable choice for demanding environments. The flat socket head minimizes protrusion and provides a clean, professional look in assemblies where space is at a premium.

For best results, pair with compatible hardware and use a proper Allen key to ensure a secure fit. These screws are designed to meet standard imperial specifications and integrate smoothly with compatible components and backing plates.