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Bolts 5/16-18 x 2-3/4 HXBT Sbr (Jar 100)
Additional Notes
- Other sizes and quantities available by request
Manufacturer Resources
Product Specs
- Arra Compliant:
- N
- Buy American Compliant:
- No
- Country Of Origin:
- MUL
- Dimensional Standard:
- ASME B18.2.1
- Division:
- Electrical H1
- Fastener Head Type:
- Hex
- Fastener Head Width:
- 0.489 - 0.500 in.
- Fastener Height:
- 0.195 - 0.211
- Fastener Length:
- 2/3/04
- Language Code:
- EN
- Material Standard:
- ASTM F468
- Order Minimum Imperial:
- 100
- Order Minimum Uom Imperial:
- CT
- Pack Type:
- Jar
- Product Family:
- Electrical Supplies
- Product Group:
- Fasteners
- Remarks:
- The catalog UPC differ from the tarnsaction daat spreadsheet UPC
- Sub Division:
- Electrical-E H2
- Thread Per Inch:
- 18
- Thread Standard:
- ANSI/ASME B1.1
- Department:
- Electrical
- Product Subgroup:
- Bolts
- Product Type:
- Hexagonal Bolt
- Type2:
- Hexagonal Bolt
- Product Finish:
- Bronze
- Product Details:
- Hexagonal Bolt
- Product Material:
- Silicon Bronze
Metallics BBH57 – Frequently Asked Questions
1) What thread does the Metallics BBH57 hex bolt take, and will it match standard 5/16-18 nuts?
The BBH57 is a 5/16-18 hex bolt, so 18 threads per inch on a 5/16 inch diameter, cut to ANSI/ASME B1.1 Unified inch thread. Any standard 5/16-18 UNC nut or tapped hole will take it. For a grounding or bonding connection, pair it with a silicon bronze nut so you are not mixing metals at the joint.
2) Why would an electrician use a silicon bronze bolt instead of plain galvanized steel?
Silicon bronze is the standard choice for grounding and bonding hardware, ground rod clamps, and outdoor connections where corrosion and galvanic reaction with copper conductors matter. The BBH57 is silicon bronze with a bronze finish, made to ASTM F468 (the material spec for nonferrous bolts). Galvanized steel against copper in a wet location sets up a galvanic cell; bronze does not.
3) Is the Metallics BBH57 bolt Buy American or ARRA compliant for a government job?
No. The BBH57 is not Buy American compliant and is not ARRA compliant, and country of origin is listed as multiple. If your federal, state, or transit contract carries a domestic-content clause, this bolt will not satisfy it and you need a domestically sourced silicon bronze fastener instead.
4) What wrench size fits the head on the Metallics BBH57 bolt?
Head width across flats runs 0.489 to 0.500 inch, so a 1/2 inch wrench or socket is the fit. Head height is 0.195 to 0.211 inch. That is standard finished hex dimensions for a 5/16 bolt under ASME B18.2.1, which is the dimensional standard this bolt is built to, so it will seat in any hardware or clamp cut for a normal 5/16 hex head.
5) How is the BBH57 packaged and what is the minimum I can order?
It ships as a jar of 100 bolts, and 100 count is the order minimum. If you need a different length or a different quantity in the same 5/16-18 silicon bronze bolt, Metallics makes other sizes and quantities available by request.
6) Will a 2-3/4 inch hex bolt be long enough for my clamp stack-up?
The BBH57 is 2-3/4 inch under the head, which covers a fairly deep stack: two bus bars, a lug, and a washer set still leave thread for the nut. Measure your total grip and leave at least a couple of threads past the nut. Because it is a hex bolt rather than fully threaded stud, plan your grip so the nut lands on thread and not on any unthreaded shank.
7) Is this a machine bolt or a lag/tapping type bolt?
It is a hex head machine bolt with a straight 5/16-18 machine thread, so it goes into a nut or a tapped hole, not into wood or masonry. If you need to fasten into a timber pole or a wood crossarm, this is the wrong fastener type and you want a lag or a through bolt with a nut and square washer.
How fast can I get the Metallics BBH57 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 BBH57 come with a warranty?
Absolutely. The Metallics BBH57 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 BBH57?
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