1.Versatile Compatibility: Our 3 to 6 inch Duct Adapter is a musthave for any Vent HVAC system. It seamlessly connects and adapts ventilation ducts of various sizes, including 3.14'', 3.93'', 4.72'', 4.92'', and 5.90'' (80 – 100 – 120 – 125 – 150 mm). It can serve as a reducer or increaser. 2.: The duct adapter is made of durable plastic, capable of withstanding temperature fluctuations and resisting corrosion. Its sturdy construction can withstand the demands of air conditioning, heating, and cooling systems. Operating temperature range: 0°C to 90°C. 3.: With our Universal Reducer Increaser Connector, installation becomes a breeze. Simply connect the adapter to your desired duct size, whether it's reducing or increasing, and seamlessly integrate it into your ventilation system. Its quick and hassle setup saves time and effort. 4.Efficient Airflow Control: The innovative design of duct inline reducer increaser connector ensures optimum airflow control. Effortlessly adjust airflow for optimized heating, cooling, or air circulation needs. Experience improved air circulation and distribution throughout your space, enhancing comfort levels and energy efficiency.