Chief CMA473 XL Plenum Rated Storage Box

The Chief CMA473 is a plenum rated storage box created for installers who need a safe, tidy place to park power bricks, extenders, and extra cable when they run gear through a suspended ceiling. It partners perfectly with Chief CMS440 and CMA440 ceiling kits, slipping into the same tile opening and keeping the area around the column uncluttered.

Because the enclosure carries a UL listing for use in air-handling spaces, it meets the strict building codes often found in offices, classrooms, healthcare facilities, and government sites. That plenum certification means you can place it above the ceiling grid without hunting for additional fire-rated enclosures.

Installation stays straightforward. The slim housing fits where space is tight, and a lid that is both flat and removable lets you set hardware or service connections without fighting a bulky cover. Knockouts sized at 0.5-inch and 1.5-inch help route data or power lines exactly where they need to go. Inside, the box accepts two dual-gang surface-mount electrical boxes, so you can mount receptacles or low-voltage plates right beside your electronics.

AV technicians, IT staff, and facilities managers will appreciate how the CMA473 keeps equipment secure, protects cables from damage, and presents a professional finish on every ceiling run. Once closed up, the entire assembly disappears behind the tile, leaving only clean sightlines in the room below.

Highlights:

• Plenum rated storage box for above-tile installations
• Designed to work with Chief CMS440 and CMA440 suspended ceiling kits
• Low profile housing with a lid that is flat and removable
• Multiple knockouts at 0.5-inch and 1.5-inch for organized cable routing
• Interior supports two dual-gang surface-mount electrical boxes
• UL listed for use in air-handling spaces
• TAA compliant for government and institutional projects