Do NOT buy!

I received my first device which did not work at all. They replaced the device and the second device did not work properly either. I requested a refund within 90 days just to be told that they only refund when you do not receive results and do not refund faulty or damaged devices. I do not have any confidence in this product as I received two devices that are either not working or that is working for less than 20 seconds. I think this is unfair to force me to be satisfied with another replacement when I have already lost confidence in the product and company when it is not even my faulth that they keep sending me a device that is damaged!