RACO 4 in. Round Non-Metallic Ceiling Box, 2-3/8 in. Deep with Expandable Bar Hanger and Ground Plate (25-Pack)

Manufactured from tough polycarbonate material. Designed to support light fixtures. Accommodate fixtures with 2-3/4 in. and 3-1/2 in. mounting holes. Mounts to a steel support bar that is adjustable from 14-3/4 in. to 22-1/2 in. Approved for use in 2-hour fire rated walls and ceilings.