- Design includes 1/2" drywall lip and rounded corners for added safety.
- Opening 1/4" oversized to accommodate filter grilles.
- Dual bead box design for added strength.
- Black diffuser board coated with EPA-registered, anti-microbial, protective acrylic agent along air stream side.
- R6RAB: R6 return air box with 4.5" tall body.
- R6RABT: R6 return air box with 9.25" tall body.
- R4/R8 model also available.