Product review (5 stars): Good vent hose for litter box
Unlike everyone else here, I did not buy this as a ferret toy. I might have, but the state of california does not allow pet ferrets. I bought this to vent stank from my litter box to outside my window.

If you're buying this for a cat box too, I used a can of pumpkin pie mix (2 pies worth) to stick into the side of the box and this fit PERFECTLY over it. It traps the air nicely and does not seem to leak at all. It can be compressed to less than 8' long without restricting airflow.