The universal reducer used for ventilation systems is 80 to 200 mm in diameter.The diameter of the different diameter of the different diameter is 80/110/120/130/140/150/160/170/180/190/200 mm, decreasing or increasing.Transition ventilation pipe circular tube ventilation pipeThe working temperature range is wide (-20°C to +65°C), and the year round is quiet, comfortable and ventilated and efficient.It can be used with HVAC system: bathroom exhaust fan, built-in fan, hood, dryer, hydroponic system, kitchen or apartment, home or office.Safe and reliable.Lightweight, quick and easy to install. Applicable to all ventilation system components. It can be used with HVAC systemEasy to cut and install: The plastic is very soft but sturdy, so you can easily use a knife several times on the edge of the diameter you need, instead of stuck or damaging the device in the wrong position