The CHKO18124 is an 18 x 12 x 4 inch hinged-cover box, the tallest CHKO size built at a 4-inch depth. It is a Type 1 mild steel junction box from the CHKO series, designed for general purpose indoor commercial use as a junction, pull or switch box, and its hinged cover with latch gives electricians easy access during installation and later maintenance.

The body measures 18 in x 12 in x 4 in (457 mm x 305 mm x 102 mm) H x W x D and is formed and spot welded from 16 gauge steel. The full-swing hinged door, about 18.38 in x 12.30 in on the drawing, closes with a slotted quarter-turn latch, and the drawing shows an overall depth of 4.11 in with the door fitted. Enclosure and cover are finished in ANSI 61 gray powder coating.

Easily removed knockouts are provided on all 4 sides; the part drawing for this size calls out knockout diameters of 0.76, 1.01, 1.13, 1.26, 1.38 and 1.75 in. Through holes in the back (0.28 in diameter on the drawing) allow wall mounting, and a grounding location is embossed in the body. Hammond notes the former butt hinge has been transitioned to a new integral hinge design starting late 2020.

The CHKO18124 is listed to UL-50 Type 1 (UL File E65324) and CSA Type 1 (CSA Cert. LR21001), and complies with NEMA Type 1 and IEC 60529 IP20. It is REACH and RoHS compliant, ships at 12 lbs (5.44 kg) and is packed in a box. A Type 1 Lock Kit and CS Perforated Panels are listed as accessories for the series. If you need the same 18 x 12 in face at a different depth, the series also lists the CHKO18126 at 6 in deep.