Now I dont have to continually ask them to "turn it up, please. It is red when it needs charging, but it is in fact blue when fully charged. I had been looking for a perfect pair of slippers for my plantar fasciitis and a touch of a heel spur. Dissapointed whereas I was thrilled with the last pair Its very difficult to get the bases to fit. There are no written instructions but it’s easy to figure out how to put together. This ended up being a surprising purchase. I’ve been using this trimmer belt for about two to three weeks now, I haven’t seen any drastic results but it definitely makes my mid section sweat a lot more than it did without it. 💦 Completely flat.