What a great product! I never would have believed that a hot/cold pack could be made with a base filling of oatmeal, but it works very consistently well. We've only used it for heat so far. I would have assumed that the filling would "dry out" or something, but it somehow produces moist heat every time. I also like the fact that there is no liquid gel filling (whether toxic or not) that tends to eventually leak out from other traditional hot/cold packs. Two of us have been using on & off for about a year, and it still seems to work like new. Very happy.