3/8ft x 12ft (50 Pack) Galvanized Carriage Bolt Kit - Durable Exterior

In this review the reviewer looks at a 50 pack carriage bolt kit sized 3/8' x 12' and aimed at outdoor carpentry projects. The bottom line: this kit is for homeowners and builders who need long, corrosion-resistant carriage bolts for decks, pergolas, fences and similar heavy duty uses. The single biggest reason to buy is the hot dip galvanized coating paired with Grade 307A bolts, which together provide superior corrosion resistance and long-term durability in exterior environments.

Key Features

• Diameter and length: The 3/8' diameter and 12' length make these bolts suitable for joining thick timbers and multi-piece assemblies without needing extensions.
• Hot dip galvanized coating: The heavy zinc finish offers strong protection against rust and pitting for outdoor exposure.
• Complete kit: Each pack includes 50 carriage bolts, 50 USS thick washers and 50 hex nuts to provide everything needed for multiple fastenings.
• Flat head design: The carriage bolt flat head provides a semi-flush finish that reduces snagging and improves appearance on deck and fence rails.
• Grade and hardware match: Grade 307A carriage bolts paired with grade 2 hex nuts and USS washers give a balanced combination of strength and value.

Who It's For

This kit is best for DIY homeowners, fence installers, deck builders and hobbyist woodworkers who need reliable exterior fasteners in bulk for projects like decks, gazebos and pergolas. The 12' length fits situations where multiple boards or thick posts are fastened through, and the hot dip galvanized finish suits outdoor environments.

Those who should look elsewhere include users needing stainless steel hardware for marine saltwater exposure or applications requiring metric sizes or finer strength grades than Grade 307A. If you only need a few bolts rather than a 50 pack, a smaller quantity option may be more economical.

Pros & Cons

Pros

• Good corrosion resistance from the hot dip galvanized finish, making the kit suitable for exterior use.
• Complete kit with washers and nuts saves time sourcing matching hardware.
• Flat head carriage bolts provide a neat, semi-flush appearance for finished work.
• Customers report solid quality and value for money for fence and deck installations.

Cons

• Washers received mixed feedback from some customers, suggesting occasional quality variation.
• Grade 307A and grade 2 nuts are suitable for most projects but may not meet high-strength structural specifications.

Specifications

Diameter	3/8'
Length	12'
Head diameter	0.813'
Nut wrench size	9/16'
Washer outside diameter	1'
Kit contents	50 carriage bolts, 50 USS thick washers, 50 hex nuts
Coating and grade	Hot dip galvanized, Grade 307A bolts, grade 2 nuts

Our Verdict

This 50 pack carriage bolt kit is a practical, value-oriented choice for anyone building or repairing outdoor wood structures. The 3/8' x 12' size, complete hardware set and hot dip galvanized finish make it a dependable option for decks, fences and pergolas, offering good durability at a reasonable price for most residential and light commercial projects.

Frequently Asked Questions

Are these bolts suitable for exterior use?
Yes. The hot dip galvanized coating provides strong corrosion resistance for outdoor applications.

Do the nuts and washers come included?
Yes. Each pack includes 50 hex nuts and 50 USS thick washers matched to the bolts.

What wrench size is required?
The hex nuts use a 9/16' wrench size.