3/8 in x 5 in Carriage Bolt Kit (25 Pack) - Ceramic Black Rust Defense

Our review of this 3/8 in x 5 in carriage bolt kit focuses on outdoor builders and DIYers who need a corrosion-aware, heavy duty fastener for structures that remain exposed to the elements. The kit delivers a simple, complete fastening solution with 25 Grade 307A carriage bolts, matching hex nuts and USS flat washers, and a 5-layer ceramic black ruspert coating that aims to provide twice the rust resistance of galvanized hardware. For anyone installing decks, pergolas or a small structure where a semi-flush carriage bolt head is preferred, this kit removes the need to source matching washers and nuts separately.

Key Features

• Complete kit: Includes 25 carriage bolts, 25 USS thick washers and 25 hex nuts so installations can proceed without hunting for matching parts.
• Durable coating: The 5-layer ceramic black ruspert finish adds enhanced rust resistance intended to outlast typical galvanized options for exterior use.
• Standard dimensions: 3/8 in diameter and 5 in length give predictable strength and fit for common structural timber connections.
• Flat head finish: The carriage bolt flat head offers a semi-flush appearance suitable for decks, gazebos and pergolas where a clean exterior surface is desired.
• Hardware grades: Grade 307A carriage bolts paired with grade 2 hex nuts and USS washers match common strength expectations for light to heavy residential projects.

Who It's For

This kit is aimed at homeowners, deck builders and small-structure contractors who value a matched set of carriage bolts and prefer a black, low-profile head for outdoor projects. The 3/8 in x 5 in size is commonly used in ledger attachments, pergola beams and post connections where a through-bolt is required.

Those needing structural fasteners for engineered, high-load commercial projects or with uncommon thread or nut grade requirements should look for certified structural bolts or higher-grade nuts; this kit is best for typical residential and light commercial applications rather than specialized industrial specs.

Pros & Cons

Pros

• Well matched kit saves time and ensures compatibility between bolts, washers and nuts.
• 5-layer ceramic black ruspert coating improves exterior corrosion resistance versus standard galvanized finishes.
• Flat head carriage design gives a neat, semi-flush exterior appearance on wood surfaces.

Cons

• Some customers report mixed results on long-term rust performance, so in extremely harsh coastal environments additional protection may be needed.

Specifications

Our Verdict

This 3/8 in x 5 in carriage bolt kit is a practical, value-packed choice for DIYers and contractors working on decks, gazebos, pergolas and similar outdoor projects. The included washers and grade-matched nuts reduce hassle, and the ceramic black coating offers improved rust resistance over galvanized hardware for most exterior uses, making it a sensible purchase for typical residential applications.

Frequently Asked Questions

Are the nuts and washers included?
Yes, the kit contains 25 USS thick washers and 25 hex nuts matched to the carriage bolts.

Is the coating suitable for coastal use?
The 5-layer ceramic ruspert coating provides enhanced rust resistance compared to galvanized finishes, but customers in very corrosive coastal conditions may want additional corrosion protection or higher-spec fasteners.

What head finish does the bolt have?
The bolts have a flat carriage head for a semi-flush appearance ideal for outdoor wood structures.