My basket looks a lot like this without the opening on the side. I carried Caramel, who was a big hen, in it for a two hours ride to the vet.
Although it was an awful trip.for her, I think the basket was much more confortable than a pet carrier would have been , it was very hot and it's much more breathable. The fact that she was held tight was actually very reassuring because we have a lot of turns on our mountain roads and I think she would have been swung around in a bigger space. I put news paper and hay on the bottom, and anyway she barely pooped throughout the ride.
The only downside I saw was that in case of an accident she would have been far less protected than in the pet carrier.
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