Machine washable! It is an electrically heated cat magnet and human warmer.
My favorite cat just emphasized the importance of easy washability by vomiting on the (unheated) blanket on my legs. She was calmly napping, then suddenly sat up, and started vomiting. She then ran to the litter box.
I just gave catnip to all of our cats. I put hers on a cardboard cat scratching surface. I hope the digestive issue was just due to consuming cardboard and catnip, and not an indication of illness.