B-Line Eaton series strut channel, nuts, all threaded rod, Steel, Tall channel nuts, Standard nut, Electro-plated zinc finish, 8"-32 thread size

The N721ZN is a steel channel nut with an 8"-32 thread size, so it mates with 8-32 machine screws or threaded rod of that thread. It is the plain standard nut version (no spring), so you hold it in the strut yourself while you start the fastener.

Check the nut body against your channel slot before ordering: the N721ZN measures .721 in wide, .425 in high and .92 in long. The width is what has to pass into the channel throat and turn a quarter to seat behind the inturned lips, and the .425 in height is what it takes up inside the channel. It is a tall channel nut, so it sits deeper than a thin nut and grips more of the lip.

Plain. It is catalogued as a standard nut, meaning there is no spring to hold it in position while you thread the screw. For overhead work where you cannot get two hands on it, a spring-loaded channel nut is the easier choice; for bench or accessible runs the standard nut does the same job with less cost and no spring to fight.

The finish is electro-plated zinc, which is a light coating intended for dry indoor service, interior electrical rooms, ceiling hangers, plenum runs and the like. For exterior, wash-down or corrosive areas you want a hot-dip galvanized or stainless channel nut instead, since electroplate will not hold up to sustained moisture.

The nut alone is just the anchor point in the strut. You still need the fastener that threads into it (an 8-32 screw or rod of matching thread), the strut channel itself, and whatever clamp, strap or hanger the load calls for. Nothing is included with the nut beyond the nut, and no washer is supplied.

Eaton B-Line part N721ZN. The ZN suffix is the electro-plated zinc finish, and the nut is steel with an 8"-32 thread. Order by that number if you are standardizing a strut package across a building.