**Red Alert**, consumers! When the Thumper company warns you in the instructions not to do something with this device, pay careful attention. In the directions, it warned against using on the legs in a downward motion and only to use it in an upward motion. It also warned against pressing too hard. Foolishly, I did not heed these warnings as my legs were in much pain. Life-changing consequences for me for not paying heed to the warnings. I ended up giving myself pitting EDEMA both of my legs. In turn, the pitting edema has caused POLYURIA. This is not a matter to take lightly. This is a life damaging consequences of me not obeying the instructions. Now my legs are in constant pain and water is collecting in both of the legs. I urinate frequently but especially the moment I lay down because that water in my legs needs to go somewhere. Try getting a good night's sleep with freezing cold feet most nights and the constant need to urinate 8 to 10 times a night. Serious serious consequences. So consider yourself forewarned and don't do what I did.. A former model and dancer, I now have 10" circumference cankles and pitting edema as a direct result of MISUSING THE PRODUCT against the manufacturers warnings. So take my warning and save yourself a lot of pain, heavy heavy legs from the water retention and now footwear that does not fit and now legs that are constantly freezing; particularly, freezing feet and calves on both legs. All this because I did not obey the instructions and heed the warnings seriously. My legs hurt before and that's why I was pressing hard with the device and going up and down. What I ended up doing was damaging my veins and calling the water from my torso down into my legs and it's sitting there permanently now. Where my leg on the left attaches to my torso, a lot of pain. Both legs painful but that area in particular. Again, bad bad circulation from the knees down. Socks hurt. Feet freezing. Most nights so be careful and know that winter boots that are too tight will make your feet freeze too. I got myself in a real pickle and I have no one to blame but myself. This is a very good product but again, take it from this regretful consumer, I wish I had heeded their very stern warnings: 1) do not use on your legs in an up and down motion. Avoid going downward on your legs with this device at all times. 2) do not press hard while using this device. It will indeed cause damage and irreparable damage in the form of edema in your legs. Red alert and beware. Forewarned. **** While amazing percussion for pain relief, I'm too weak at the moment to comfortably hold it. It's 3 LBS. I'M HESITATING TO RETURN THIS because it's so amazing but I want to be able to use it comfortably on my own and I can only lift it while laying down because MS has stolen all my strength. I love that it plugs in and does not require a battery and the cord is very long which is convenient.