I purchased this for my 80lb Lab Mix. He has damaged his knee and the vet feels he is too old to consider surgery to fix it. The vet had recommended a custom brace that was over $1,000 but when I saw this wheelchair, I thought it was worth trying. Turns out, it is the PERFECT solution! The wheelchair is very well made and durable and supports the weight of my dog easily. There is a slight learning curve for you until you get it adjusted perfectly, but then it is very easy to use. I have a bad shoulder, but am able to get my 80lb dog in and out of the chair by myself without issue. The chair supports their back end and can be used as a walking aid (with all four paws on the ground) or as a full wheel chair by putting their feet into the little slings provided so that they are only using their front legs to walk. My dog uses it with all four feet on the ground and it has been a lifesaver! It is the perfect tool to aid him with walking, even outside and provides him with support while he does his potty business. The only downside is that the chair is very light and he once tried to go up stairs in it and ended up almost flipping over. So be sure that they cannot get to stairs or drop-offs unless you are within arm's reach to stop them. Otherwise, it is great! We use it outside in our yard and walking trails in the woods, both uphill and down. This was a great investment and has improved my dog's quality of life a lot.