The baseboard diffuser, also called baseboard register, is designed for use in homes where duct openings are located at the edge of the floor or at the base of the wall. Available Wood Species: Solid wood species: white oak, red oak. Available Finishes: Unfinish, natural finish, or other prefinish. Size Available: 15" 18" 24" Customized service: Dimensions, wood species, finishes, and other specifications can be customized according to customer's drawing, welcome OEM production.