Metallics JW119SSD Washers 3/8 X 1-1/4 Fender SS (Jar 100)

The JW119SSD is a 3/8 inch fender washer, so it goes over a 3/8 inch bolt or threaded rod. The 1-1/4 inch outside diameter is what makes it a fender washer rather than a standard flat washer: it spreads the clamp load over a much wider area, which is what you want in sheet metal, drywall, soft wood, or a slightly oversized hole where a standard washer would pull through.

Stainless steel, so they hold up outdoors and in damp locations far better than plain or zinc-plated steel. Pair them with stainless bolts and nuts where you can, since mixing stainless washers with plain steel fasteners just moves the corrosion to the weaker part.

Same 3/8 inch bore, much bigger face. A standard 3/8 USS or SAE flat washer has an outside diameter well under an inch; the JW119SSD runs 1-1/4 inches across. Use the fender washer when the material under it is thin or soft (metal studs, strut hung off drywall, plywood backing) or when the hole was drilled oversize. For bearing against structural steel or a machined surface, the standard flat washer is the right part and the larger face buys you nothing.

Yes, that is a common use. On 3/8 inch rod the washer seats under the nut and spreads the load, which is useful where the rod passes through a wider hole or through thinner material than the nut face can bear on. Being stainless, it also suits wet and exterior support points. It is a washer only, so rod, nuts, and strut are separate items.

100 washers per jar, packed in a screw-top jar rather than a loose bag, which is why it stays usable on a cart or in a gang box. The full jar weighs 1.37 lbs.