4-40 X 3/8″ Socket Cap Screws Flat Head Hex Socket Drive Nylon Patch Alloy Steel Thermal Black Oxide (200 / Pkg.) Save Now

Cap Screws Flat Socket Nylon Patch Alloy Thermal Black Oxide 4-40 x 3/8 are precision-engineered flat socket cap screws designed for secure, high-precision fastening in a variety of assemblies. Featuring a nylon patch backing, alloy construction, and a thermal black oxide finish, these screws offer reliable performance in demanding environments.

Key benefits include enhanced load distribution, reduced vibration, and protection of mating surfaces thanks to the nylon patch. The 4-40 thread size and 3/8 inch length make these screws ideal for electronics, automotive, and industrial applications where a compact, corrosion-resistant fastener is required.

Features

Thread size: 4-40

Length: 3/8 in

Head style: Flat Socket Cap

Material: Alloy with Nylon Patch backing

Finish: Thermal Black Oxide

Applications: Electronics, machinery, enclosures, and more

Why choose these cap screws?

They combine strength, durability, and a non-marring backing for sensitive surfaces. The thermal black oxide finish provides corrosion resistance and a low-reflectivity appearance, making them suitable for both functional and aesthetic demands in professional assemblies.

Specifications

Thread type: 4-40

Length: 3/8 in

Head: Flat Socket Cap

Material: Alloy

Finish: Thermal Black Oxide

Backing: Nylon Patch