Wooden Filter Grille This wooden grille features bold lines that are a perfect accent to any home, as well as a detachable faceplate. They are made of white oak, red oak, cherry or maple with unfinished finishes. Size in 12x20” Mental damper can be supplied. We also supply wooden baseboard diffuser, wooden wall returns, wooden wall return, floor registers, egg crate floor registers, Single Deflection Floor Register