On cold winter nights, keep the chills away with this safe and efficient warming mattress pad. The queen-sized Soft Heat warming pad provides continual and even bed warmth through the night. To operate, the warming pad is equipped with two computerized, lighted controllers and two 8-2/3-by-2-1/2-by-3-inch power supply boxes which convert the 120-volt AC home current into a non-hazardous, low voltage DC current. The two-controller design allows bed occupants with different heat preferences to set and adjust temperatures for each side of the bed; heat levels increase from 1 to 9 with additional LO and HI settings. For cozy sheets before bed, the mattress pad has a 15-minute automatic preheat and hold function. The warming pad benefits from over-temperature protection that stops operation. It also automatically shuts off heat after ten hours for extra safety, user convenience, and power conservation. The mattress pad is crafted in soft 233-thread-count 80-percent polyester, 20-percent cotton blend in white with a dobby stripe weave. In contrast with the bulky wires of traditional electric blankets and heat pads, the Soft Heat warming pad benefits from ultra thin wires that are virtually imperceptible to bed occupants. A fitted skirt holds the pad in place and accommodates mattresses up to 18 inches thick. Safe for machine washing and drying, the mattress pad resists pilling, shrinking, and stretching for long use. The mattress pad is not suitable for use on waterbeds, inflatable mattresses, and fold-out sofas or other adjustable beds (though okay for Sleep Number beds), and it should not be combined with other electric blankets or pads. Available also in twin, full, king, and California king sizes, the mattress pad is covered by a limited 5-year warranty. This item weighs 7 pounds upon shipping.