The Hammond C3R18188SCNKO is a Type 3R painted galvanized steel junction box measuring 18 in high, 18 in wide and 8 in deep (457 mm x 457 mm x 203 mm). It belongs to the C3R SC NKO Series, which pairs a lift-off cover held with screws with a body built without knockouts, for electricians, contractors and OEM builders who need a plain Type 3R box. It is designed for use as a wiring/junction box and provides protection against rain, sleet, snow and dripping water.

The body is formed and spot welded from 16 or 14 gauge galvanized steel with a drip-shield top and seam-free sides, front and back. The slip-on removable cover is fastened with plated steel screws, and both enclosure and cover are finished in ANSI 61 gray powder coating. A padlocking hasp is provided for securing the cover, a grounding kit is included, and the series is built with no gasket.

Hammond's drawing for the C3R18188SCNKO shows an overall width of 18.52 in at the top, an overall depth of 8.28 in in side view and 8.98 in in bottom view, and embossed Ø0.28 in mounting holes on the back spaced 15.69 in x 13.00 in. The shipping weight is 25 lbs (11.34 kg).

The C3R SC NKO Series is listed to UL-50 Type 3R and cUL Type 3R to CSA Standard C22.2, No. 94 (UL File E65324, CSA Cert. LL21312), and complies with NEMA Type 3R and IEC 60529 IP24. The part is REACH and RoHS compliant, and Hammond's EU Declaration of Conformity for its Commercial Enclosures (including C3RSC) cites the Low Voltage Directive 2014/35/EU. The same 18 x 18 in face is also offered in this series as C3R18186SCNKO (6 in deep).