About this 3D model

Diesel heater suction flange My diesel heater is located behind the wall. So that the heater does not suck in icy air from another room, I made a flange. Suction tube diameter 75mm https://www.aliexpress.com/item/1005006136773783.html? Attach the flange with self-tapping screws or rivets. Optional: the inner diameter of the flange for inserting the hose is 113mm.