Metallics JW1231SS Washers 3/8 x 2 Fender SS (Jar 100)

It's a 3/8 inch fender washer with a 2 inch outside diameter, so it goes over 3/8 inch bolts, rod, and screws. The oversized 2 inch OD spreads the load far wider than a standard 3/8 flat washer, which is the whole point of a fender washer.

The JW1231SS is stainless steel, so it holds up in wet and outdoor work where a plain or zinc washer would rust, such as exterior strut runs, rooftop mechanical, and damp mechanical rooms. Pair it with stainless fasteners so you aren't mixing dissimilar metals at the joint.

The larger diameter gives a much greater bearing surface. On sheet metal, plywood, drywall, soft gypsum, or an oversized or slotted hole, a standard 3/8 flat washer can pull through or dish the material. The 2 inch OD spans that hole and distributes the clamp load. If you're bolting steel to steel through a tight hole, a standard flat washer is the cheaper, lower-profile choice.

100 pieces per jar, and the jar is the pack format rather than a loose bag or box. That's a sensible MRO shelf quantity: the jar stays closed on the truck or in the shop crib instead of spilling. The filled jar runs 5.124 lbs.

The manufacturer part number is JW1231SS from Metallics. One model covers it, there are no finish or size options to pick: 3/8 inside, 2 inch outside, stainless, 100 to the jar.

Metallics lists the application as the electrical, plumbing, heating and air conditioning industries. In practice that means hanging strut and trapeze, anchoring conduit straps and panel backboards, pipe and duct support, and any spot where a 3/8 bolt or hanger rod passes through thin material and needs a wide bearing face.

The jar measures 5.75 in by 3.5 in by 3.5 in and weighs 5.124 lbs, so it fits a standard parts-bin shelf or a van drawer without repacking.