Suncourt Flush Fit Adapter Plate for Register Air Booster Fan - HC5PL1-W - White (2 pack) USE WITH SUNCOURT REGISTER BOOSTER: This product is compatible with Suncourt Flush Fit Register Booster Units. EASY INSTALLATION: Easily fits in wall and floor registers that are 6"x10", 6"x12", and 4"x12". PROFESSIONAL LOOK: Maintain the appearance of your home while boost the energy efficiency of your forced-air unit. SAFE FOR YOUR HOME: ETL Listed--count on this product in maintaining a safe home. MATCH YOUR DCOR: Available in white and brown to match your interior design.