Needed to let it air out at first due to a strong smell. Been using it now for a couple of weeks and my cat loves it! She sleeps outside all night and we also have peace of mind knowing she is safe. We had to build an extension to go from the cat flap door to her enclosure. An added bonus would be the ability to purchase add-ons like flexible/collapsible square mesh 'tubes' for faster and easier setups.