I have bought the massage roller and the tens unit, both are great at helping to alleviate back pain, foot pain and neck pain for me. As an office worker for the past 30 years these are great and as always you get what you pay for, the Chinese knock offs just don’t last, don’t have the same quality and don’t work as well. My advice, spend your money right the first time read the reviews and get the relief you are looking for.