We got the dog collar for our rescue dog who has suffered with on and off lameness for many years due to injuries caused from her previous life. We medicated the lameness whenever it presented itself but decided to give this collar a go, she was suffering from an episode of lameness the day we put it on and we decided not to medicate so we could see if the collar actually works, within 2 weeks of her wearing it she has never had a day's lameness since and that was months ago, in fact she has been better than she has been in years in general. Not even any stiffness whatsoever. If someone told us it would make this much difference I wouldn't have believed them. Honestly the best thing we have ever got for our dog. Highly recommend them to everyone.