B-Line Eaton series wiring trough, 4" height, 12" length, 4" width, GRT NK wiring trough, Embossed thru holes, No knockouts, Screw cover, 3R, Steel,

The 4412 GRT NK is a NEMA 3R trough, so it is intended for outdoor use where falling rain, sleet and external ice formation are the concern. It is not a washdown or hosedown enclosure. The steel body is finished in ANSI 61 gray and the cover seals against a flange with plated screws, which is what gives it the 3R rating rather than a gasket.

It is a 4 x 4 inch cross section, 12 inches long. That 4 by 4 opening is the working dimension for conductor fill, and the 12 inch length makes it a short pull or splice section rather than a run of gutter. It weighs 4.339 lb, so one person can hold it in place while fastening.

No. The NK in the model designation means no knockouts, so every conduit entry has to be field punched or hole sawed. Pick this version when you want to control exactly where the penetrations land, or when a 3R installation means you do not want unused knockouts on the top or sides. If you would rather have factory openings, order the knockout version of the trough instead.

It is a screw cover, not a hinged one. The cover sits against a flange and is held by plated screws that you back out to open the trough. That means you need working clearance in front of the trough and a place to set the cover during a pull, but it also means there is no hinge to sag and nothing to swing into an aisle.

The back has embossed thru holes, so it mounts with your own fasteners straight to a wall, backboard or strut run. Mounting hardware is not part of the trough, so bring lags, machine screws or strut nuts to suit the surface. The embossed holes keep the mounting points raised off the mounting surface, which is what you want on an outdoor 3R installation.

The body is 16 gauge steel, painted ANSI 61 gray. That is the usual body thickness for commercial gutter and trough of this size, and it holds its shape when conductors are packed in and pulled through. It is also CSA Certified, which matters if the job is spec'd for Canadian jurisdiction or an inspector is looking for a listing mark.

It is finished in ANSI 61 gray, the standard gray used across most commercial electrical enclosures, panel fronts and gutter. For a property manager or MRO buyer adding a section to an existing run, it will read as the same color family as the surrounding equipment rather than a mismatched piece.