kheoed built-in register booster fan with cover for air heat vent with fan,fits 4"x10" duct/ceiling/floor vents, improves ac & heating/cooling,quiet 10-speed household/bedroom ventilation,smart,bronze is up for auction in Tools & Home Improvement. The current bid is $4.50, 91% below the $49.99 MSRP, in New/Like New condition. This auction has ended — similar items appear in live auctions regularly.