I originally purchased this cupping device to help me manage pain outside of a physical therapist's office. I have been struggling with pain in my trapezius and rhomboid muscles, as well as tennis elbow from overuse. I tried the device on its own without reading the instructions first and was scared to death. The suction is strong and it wouldn't release immediately, leaving a bruise. However... my husband applied it to my back a few days later and, aside from the expected suction marks, the lingering pain had subsided by the next day. I have been dealing with these issues since April 2023 and the results have been surprising for such a small but powerful piece of equipment. It is easy to use, convenient, and works well with lube or massage oil, so it glides easily over the skin's surface. My husband is a personal trainer and now swears by this product after a workout! We have added it to our home therapy regimen and plan to use it to soothe sore muscles, avoiding unnecessary medical expenses and trips to a physical therapist. Great product.