B-Line Eaton series Type 3/3R junction boxes, 6" height, 4" length, 6" width, 3 and 12, Screw cover, SCG enclosure, Surface mounted, Small single doo

It measures 6 inches high, 6 inches wide and 4 inches deep, and weighs 4 pounds. The 4 inch depth is the number to check first: with conduit hubs, wire nuts or a small terminal strip inside, that depth sets how much bending room you have behind the cover.

No. The 664 SCG has no mounting provisions, so there are no factory feet, brackets or mounting holes in the back. It's a surface-mount box, which means you either drill the back yourself and seal the fasteners, or order separate mounting feet. Plan that into the job before you get to the wall, since drilling the back of a gasketed enclosure can compromise the 3/3R rating if the penetrations aren't sealed.

It ships as a blank galvanized steel box with a screw-on cover, no knockouts called out. For a gasketed 3R enclosure that's normal, since holes are punched in the field where the conduit lands and sealed with watertight hubs. Budget for hubs or sealing locknuts on every penetration if you want to keep the outdoor rating.

A screw cover like the 664 SCG suits pull points and splice boxes you rarely open, and the gasketed screws give an even clamp on the gasket all the way around. If the box holds a device someone accesses regularly, a control station or a disconnect, take a hinged-cover enclosure instead, because pulling and reinstalling a dozen screws each visit is where gaskets get damaged and covers get left loose.

The body is 14 gauge galvanized steel, left unfinished in a grey mill appearance rather than painted. Galvanizing handles ordinary outdoor exposure and damp industrial air, but it isn't the right pick for coastal salt spray or chemical service. For those, go stainless or a fiberglass/polycarbonate Type 4X box.