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Washer 5/16 Flat SAE Wshr Extra Hvy D (Jar 100)
Manufacturer Resources
Product Specs
- Division:
- Electrical H1
- Pack Type:
- Jar
- Product Group:
- Fasteners
- Sub Division:
- Electrical-E H2
- Department:
- Electrical
- Product Subgroup:
- Washers
Metallics JSWHH74 – Frequently Asked Questions
1) What bolt size does the Metallics JSWHH74 flat washer fit?
The JSWHH74 is a 5/16 inch SAE flat washer, so it pairs with 5/16 inch bolts, screws, and threaded rod. SAE pattern means a smaller outside diameter and smaller hole than a USS washer of the same nominal size, so it bears closer to the fastener head rather than spreading load as wide.
2) Will a 5/16 SAE washer work with a 5/16 USS washer pattern hole or oversized slot?
Not well. SAE washers have a smaller outside diameter than USS, so over an oversized hole or a strut slot the SAE washer can sit partly unsupported or pull through. If you are bridging a slot or an oversized hole with 5/16 hardware, use a USS pattern flat washer, which has the larger OD, instead of this SAE one.
3) What does extra heavy duty mean on a 5/16 SAE flat washer, and when do I need it instead of a standard one?
Extra heavy duty refers to a thicker washer than a standard SAE flat. The extra thickness resists cupping and pull-through when you are torquing hard, clamping through sheet metal or strut, or bearing against a soft or slotted surface. For light trim and general assembly a standard 5/16 flat is enough; for structural standoffs, strut and channel hangers, and anything carrying real load, the extra heavy pattern is what you want.
4) How does the Metallics JSWHH74 washer come packaged, and how many are in it?
It ships as a jar of 100 pieces. The jar pack is the handy size for a van or a gang box, which is how electricians and maintenance crews usually buy 5/16 washers rather than taking a bulk box.
5) Is this 5/16 washer suitable for electrical rough-in work like strut, hangers, and panel mounting?
Yes. The JSWHH74 is stocked as an electrical fastener, and a 5/16 extra heavy flat is the washer typically used with 5/16 hardware on strut and channel, beam clamps, conduit hangers, and equipment mounting where you need a thick bearing surface under a nut or bolt head.
6) Do I need a lock washer too, or is this flat washer enough?
A flat washer like the JSWHH74 spreads the clamp load and protects the mating surface; it does not resist loosening. On vibration-prone equipment mounts, pair it with a split ring or tooth lock washer, or a nylon insert lock nut, under the nut side. The flat washer goes against the material, the locking element against the nut.
How fast can I get the Metallics JSWHH74 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 JSWHH74 come with a warranty?
Absolutely. The Metallics JSWHH74 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 JSWHH74?
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selection,
installation tips, and troubleshooting. Contact Us
Why buy the Metallics JSWHH74 from ZenSupply?
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