Metallics JG8WW80 Washers 1/4 G8 USS Flat St-zn (Jar 100)

The JG8WW80 is a 1/4 inch flat washer, sized to the USS pattern for 1/4 inch bolts and threaded rod. It ships 100 pieces to a jar, which is the practical pack for a service van or a shop bin rather than a bulk box.

Hardened steel, Grade 8. That matters when you are torquing a Grade 5 or Grade 8 bolt down onto a strut channel, a beam clip or a seismic brace, where a soft washer dishes and loses clamp load. For light-duty wood or sheet metal work a plain low-carbon USS washer is all you need.

It carries a zinc chromate finish over hardened steel. That is a plated coating suited to dry interior and protected work, such as panel rooms, mechanical rooms and interior hanger runs. In wet, coastal or chemically exposed locations, stainless or hot dip galvanized hardware is the correct call instead.

USS pattern washers are the wider of the two standard flat washer series, so a 1/4 inch USS washer spreads load over a larger footprint than an SAE washer of the same bolt size. That is what you want over slotted strut, punched angle, or any oversized or field-drilled hole. If the bearing surface is tight, say inside a small bracket or a recessed boss, an SAE washer is the narrower option.

Metallics lists this washer for the electrical, plumbing, heating and air conditioning trades. In practice it is the washer that goes under nuts on all-thread hanger rod, strut fittings, box and panel mounting bolts, and equipment anchor bolts. It is a general purpose wrought flat washer, not a lock or spring washer, so pair it with a lock washer or a nylon insert nut where vibration is a concern.

One hundred washers per jar, at 0.61 lbs for the container. The jar format keeps them sorted on a truck, and at that count it suits a punch list or a moderate hanger run rather than a full building rough-in, where you would want to order multiple jars.