This publication covers guidelines for the selection and installation of general-purpose and specialty metallic, nonmetallic, and composite outlet boxes, including device boxes, boxes for luminaires or other products, junction boxes, extension rings, covers, and flush-device cover plates. The boxes addressed in these guidelines are intended for use in ordinary, non-hazardous locations. With the exception of masonry boxes and some multi-gang boxes and floor boxes, the boxes addressed in these guidelines are limited to 1,650 cm³ (100 in³) internal volume per gang. There may be no other component of our electrical distribution system that serves more purposes than the electrical outlet box.