Product review (2 stars): Too small for a 2 year-old.
I bought this to keep in the car but it's really too small for my 2 year-old.  The opening is too small for her to keep stable on and it can easily tip over.  As the other reviewer mentioned you can't twist it too much or it does come apart easily.  We never used it so I returned it.  Decided to go with the Baby Bjorn Smart potty seat and it works great for the car.