The packing says don’t use for longer than 20 min. at a time – believe me it stays very cold for at least that long – and I wrap it in a towel when I use it. I’ve got a very bad back and I’ve tried at least 5 other types and this is by far the coldest one I’ve found. Seems to refreeze quickly also. Love it.
I’ve been using this for almost a year , love it . I have severe osteoporosis and have had shoulder surgery . They say not to use it more than 20 minutes , it is extremely cold . I wrap it in a towel and sleep on it . It say cold for several hours . Wish they made a bigger ! I need a mattress size !