This cat flap is great as said before to keep intruders out! I had been noticing my little Princess was always nervous around her old cat flap and looking out before she ate her food probably because there have been theifing cats in her home! The lock and magnetic solution is really effective. Princess had never worn a collar before and has taken to the collar very well, she was reluctant to go through the flap as she couldn't grasp the idea of the flap so it took a little time for her to adjust I think this is due to her being nervous of other cats. Over all this is a great flap for your cat and the price is amazing would recommend training your cat to use it before fitting. Princess now goes through confidently after a day or two! Thanks so much :)