This is a 3D printed heater duct for vehicle heaters, like a Propex. It allows a better transition between the bulk head and the output/input of heater ducting.
In action: https://youtu.be/F95AqgCRM38
Webasto part #9009239B required and can be found on Amazon.
Please note this part is made to order and may have a 1-2 week lead time.
Warnings This is a 3D printed part made from carbon fiber infused ABS plastic, because of this there limitations that must be understood. The duct cannot exceed 221ºF, doing so will cause deformation and possibly failure. Therefore the duct must be placed at an appropriate distance from the heater to avoid this. Care must also be taken not to over tighten the part to avoid breaking it as well.