Review on FinYii No-Mess Automatic Bird Feeder - Premium Parrot Feeder Cage Accessories for Parakeet Canary Cockatiel Finch - Hassle-free Bird Feeding Solution by Ryan Hampton

Definitely only for small birds. I wouldn't go for more than one budgie on these. Fitting was easy enough, I would measure the door opening before purchasing to make sure it would fit. Fiddling with the screw required some dexterity that I seemed to lose, and since it potentially left my door open to little escape artists I had to secure the door with a clamp or something. Otherwise, it took the birds some time to get used to it, but eventually they realized that the food came out regularly. I had to lure them with millet, but in the end they got it. I was content with this knowing I wouldn't be home for the weekend and feeding the birds.