Bed Warmer 18 in x 36 in with canvas cover and Single-Heat setting is the perfect solution for people with poor circulation or cold feet. 18 x 36 size works two ways: Perfect fit for one side of the bed when one of you wants more heat that the other or you can lay the Bed WarmerTM across the bottom of the bed to share your warm feet and legs. Low consistent heat rises up so it warms the entire area, not just the top of your legs. No need to heat up the whole bed or raise the thermostat setting just to keep your feet warm. Out of the way placement under the sheet and mattress pad. 10 foot cord makes it easy to reach a wall socket. Placed under the bottom sheet, the gentle heat rises to give you cozy warmth right where you need it for just pennies a day. Diabetes, Peripheral Artery Disease, Arthritis, Chronic Fatigue Syndrome, Fibromyalgia, Reynaud's Disease, Multiple Sclerosis, Restless Leg Syndrome and many other problems can benefit from the soothing warmth of the BedWarmer. The fleece outer cover should always be used. Please use caution if you have delicate skin or are sensitive to heat.