OPTIMAL SOLUTION: A quiet fan system designed for improving wall and floor register airflow from HVAC systems; Ensures every penny spent on your electricity bill contributes to improved comfort; As a year-round practical gadget, VELLEE Register Booster Fan will also help in winter months SMARTER: With a high-sensitivity temperature sensor and custom-designed smart chip, the fan automatically starts and stops according to your settings, maximizing indoor temperature balance and energy savings - no frequent setup; no need for gimmicky APP - no added burden on your nearly full phone QUIETER: Upgraded by a 22-year-experienced team, the high-static-pressure PWM motor ensures efficiency (up to 200 CFM airflow) while minimizing noise (as low as 18 dBA), ensuring a peaceful sleep. Even lower noise? Simply lower the fan speed (10 levels adjustable) EASIER: Effortless installation, no professional assistance needed. Refined setup steps based on feedback from 1,000 initial users make it easier than competitors; Minimalist remote control design avoids confusion with panel button operations; ->>> IT NEEDS TO BE PLUGGED IN AN OUTLET (wall adapter & 12 ft cord included) MORE TRUSTWORTHY: Honest. Efficient. Transparent. VELLEE specializes in register booster fans, committed to ensuring you feel expected value and supported. SIZE MATTERS! To select the correct size, first remove the existing vent and measure the DUCT OPENING. Then, compare your measurements with "PRODUCT SIZE" listed on this page >>> The dimensions of this, or any other, register booster fan are categorized by the size of the DUCT OPENING (for example, 6" x 10"), not the face of the vent cover. Before purchasing, please remove the old vent cover and measure the duct opening. Verify that the duct opening has enough space to accommodate the neck of the product [Neck (Length x Width x Insertion Depth): 9.72" x 5.63" x 1.96"], and check for any obstructions, such as steep inward taper, that could stop the neck fitting >>> PRODUCT SIZE OF MODEL 6" x 10": Screw Hole Spacing: 10.95" - Neck Insertion Depth: 1.96" - Neck (Length x Width): 9.72" x 5.63" - Face (Length x Width): 11.98" x 7.92" (The neck is the section that goes into the vent hole while the face is what will actually cover) >>> USAGE SCENARIOS AND LIMITATIONS: A register booster fan is designed to complement your home's HVAC system. In line with our values of honesty and efficiency, we want to be transparent: If your ducts are not properly sealed or insulated, the fan may not enhance your room's comfort as expected VELLEE register booster fan is a valuable addition to any home's HVAC system. Its efficient temperature control, quiet running, smart features, and easy installation make it a standout product. If you're looking for a solution to eliminate temperature inconsistencies and improve the efficiency of your HVAC system, this register booster fan is a fantastic choice. Your home's comfort and energy efficiency will benefit greatly from this product! With VELLEE register booster fan, this summer, neither you nor your family will wake up drenched in sweat. Plus, as a year-round practical product, it'll provide assistance during the winter months too. It needs to be plugged into an outlet (Wall Adapter & 12 ft Cord included). Size matters! Measure first and then select correct PRODUCT SIZE - Fits only 6” x 10” vent openings.