For full transparency I was gifted this product, not by the company themselves, but by a friend.
We have a 15 and a half year old Pointer, who has always had various joint issues. Currently he can just about wobble around our house, and needs a set of wheels to get out on a walk. He has been deteriorating recently and we see him find things harder and harder. Quality of life is our main priority for him, and he's on various pain medications to help.
I'll be honest I thought it would be a bit of a waste of product as this is old age, not something that can be "healed", however within 1 week, he was brighter and a little more able, which I'm putting down to extra pain control. He seems more stable, and has started doing little things he hasn't for a while, like shouting when he wants to go for a walk etc.
The difference in him is so noticeable, my 81 year old mother who sees him weekly was astounded by the improvement, and immediately asked me to order her some Tvati for arthritis in her hands. Another friend now has also ordered, and I'm waiting on more for Charles the Pointer too.
This is a very remarkable product. I have no idea how it might be working, but I really really believe it is.