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Bolts 3/8-16 x 4 Carriage Blt Galv (Jar 25)
Additional Notes
- Other sizes and quantities available by request
Manufacturer Resources
Product Specs
- Arra Compliant:
- C
- Buy American Compliant:
- C
- Division:
- Electrical H1
- Fastener Head Type:
- Mushroom
- Fastener Head Width:
- 0.782 - 0.844 in.
- Fastener Height:
- 0.188 - 0.208
- Fastener Length:
- 4
- Fastener Width:
- 0.368 - 0.388
- Hardness:
- Rockwell B70-B100
- Language Code:
- EN
- Neurspe:
- https://ideadigitalasset.com/DAMRoot/Original/10035/11237_ID-SPE-v1-ID-SPE-v1-Carriage_Bolt_St-Zn_and_Galv.pdf
- Order Minimum Imperial:
- 25
- Order Minimum Uom Imperial:
- CT
- Outside Diameter:
- 0.360 - 0.388 IN
- Pack Type:
- Jar
- Product Group:
- Fasteners
- Product Height:
- 7.25 in
- Product Length:
- 4.5 in
- Product Weight:
- 1483 g
- Product Width:
- 114.3 MM
- Sub Division:
- Electrical-E H2
- Thread Per Inch:
- 16
- Yield Strength:
- 36000 psi minimum
- Department:
- Electrical
- Product Subgroup:
- Bolts
- Product Type:
- Hexagonal Bolt
- Type2:
- Hexagonal Bolt
- Series:
- CB and JCB
- Product Finish:
- Galvanized
- Product Details:
- Hexagonal Bolt
- Product Material:
- Steel
Metallics JCB28G – Frequently Asked Questions
1) What nut thread do I need for the Metallics JCB28G?
It is a 3/8-16 thread, 16 threads per inch, which is standard UNC coarse. Any 3/8-16 hex nut, nylon insert lock nut, or coupling nut mates with it. Match the finish to the bolt (galvanized or hot dip) if the connection sees weather, or you set up galvanic wear between the parts.
2) Does a carriage bolt need a wrench on both ends to tighten?
No, and that is the point of the mushroom head. The 0.782 to 0.844 inch domed head has no driver recess; the square shoulder beneath it locks into the wood as you turn the nut, so you only wrench the nut side. On steel or an oversized hole the shoulder has nothing to grip, so use a hex head bolt there instead.
3) Can these carriage bolts be used outdoors or in a damp location?
Yes. The JCB28G is steel with a galvanized finish, which is the usual pick for exterior framing, fence and post work, outdoor equipment mounts, and damp service areas. Bare zinc-plated bolts are better kept inside.
4) How many bolts come in a jar of JCB28G and can I buy fewer?
They ship 25 to a jar, and 25 count is the order minimum, so the jar is the smallest buy. Jar packaging keeps the count honest on a truck or a gang box. Other sizes and quantities are available by request.
5) Do these bolts meet Buy American or ARRA requirements for a public project?
The JCB28G is flagged compliant for both Buy American and ARRA, which is what a government, school, or healthcare procurement file usually needs on a fastener line item. Country of origin is listed as multiple.
6) Do carriage bolts come with nuts and washers?
No. A jar of JCB28G is 25 bolts only, so order 3/8-16 nuts separately, plus flat washers for the nut side. The domed head seats directly against the material and does not take a washer.
How fast can I get the Metallics JCB28G delivered?
Most orders ship the same day from our distribution partners, with quick delivery throughout the
continental
U.S.
Need it urgently? Contact Us for expedited shipping options.
Can I return it if it doesn’t work for me?
Yes—ZenSupply offers a hassle-free return policy. If the product isn’t the right fit,
reach out to our support team for a return authorization or setup a return by following our return instructions.
Does the Metallics JCB28G come with a warranty?
Absolutely. The Metallics JCB28G is backed by a manufacturer’s warranty.
For full warranty terms, check the product documentation or Contact Us.
How do I get technical support or installation help for the Metallics JCB28G?
You can call, text, or email our expert support team for fast answers. We’re here to help with
product
selection,
installation tips, and troubleshooting. Contact Us
Why buy the Metallics JCB28G from ZenSupply?
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and
rewards on
every order.
Our team is always ready to help you choose the right product for your project.