I wanted to improve the ventilation of my Voron, but the right fan was too expensive, so I went with a 97x33 and needed to reduce the friction with the tube as much as possible to get the expected air flow.

So I used a super cheap 3/4 smooth transparent hose.

Two disadvantages: they are more rigid, so if you are looking for the fastest way to move the toolhead, this is not the best choice, and it can "bend" with creases.

It was to solve the second problem that I made these rings, they allow it to move freely and prevent it from collapsing

It worked well for me spaced 15-18mm apart