We have two labs. A two year old yellow and a 7 month old black. I have been frustrated with conventional vinyl pet doors I used in our kennel. The last one I purchased for $80 lasted less than 36 hours. (You know labs.) Finally, I found the Gun Dog House Door Co. Heavy Duty Dog Door®. I was impressed with the design, so I purchased two to get free shipping. I easily installed them on our heated kennel house last fall. They have performed as advertised. Both older dog and the pup (3 months at the time) learned to use them quickly. The solid construction is also draft-free and has held up to constant use. This is a great product and I’ve come accustomed to the clack of the door slamming. Thanks again for building a product that performs better than advertised.