Hillman 3/8-16 in. D x 6 in. L Steel Hex Head Cap Screws, 25-pack, are built for dependable, long-reaching connections in wood, metal, and mixed-material assemblies. The sturdy steel body and hex head deliver high-torque driving for fast, secure seating in demanding projects.
Designed for through-bolting and nut-attached fastenings, these screws use a coarse 3/8-16 thread that bites quickly into materials while resisting pull-out when properly seated. Measuring 6 inches in length, they traverse multiple material layers—ideal for mounting heavy brackets, plates, or equipment to framing, timber, or sheet metal.
Each box contains 25 screws, making it easy to stock up for ongoing work without constant reordering. The boxed packaging keeps the fasteners organized and ready to grab when you need them on site or in the shop.
Key specifications
-
Diameter: 3/8 in
-
Thread: Coarse 3/8-16 UNC
-
Length: 6 in
-
Head: Hex Head Cap Screw
-
Material: Steel
-
Package: 25 screws per box
-
Packaging: Boxed
What you can do with these screws
- Through-bolting brackets and hardware to thick lumber or metal plates for structural connections in decks, furniture frames, or machinery mounting.
- Attaching mounting plates, brackets, or fasteners where a robust, high-torque drive is needed.
- Assemblies involving standard 3/8-16 nuts or tapped holes—ensuring a secure lock with consistent thread engagement.
Who this is for
- DIY enthusiasts tackling home projects that require reliable through-bolts.
- Professionals and contractors needing a ready supply of hex head cap screws for shop and job-site use.
- Woodworkers and metal fabricators who value a straightforward, durable fastener for long-lasting assemblies.
Practical tips for best results
To maximize holding power and minimize material damage, consider pre-drilling appropriate pilot holes in hardwoods, ensure the target thickness accommodates the 6-inch length, and pair these screws with the correct 3/8-16 nuts or tapped holes. Align components before driving to prevent cross-threading and ensure square, clean seating with a standard hex drive or torque-rated tool.
