Two pads in one is the best way to describe this warming pad. This is one of the safest and plush warming pads you'll ever have the luxury of snuggling up on. The 233 thread-count 80% poly / 20% cotton dobby stripe shell is incredibly soft and soothing but that's just one of the wonderful features of this pad. Constructed within the pad is the patented ''Safe and Warm'' low-voltage technology. This low-voltage mattress pad includes a small power supply box that changes 120V AC home current into non-hazardous low voltage DC current (very similar to a battery) to provide warmth, protection and safety even if the pad becomes wet. Unlike other warming pads with their bulky wires, the heating wires in the Soft Heat pads are so small, they are virtually unnoticeable and also give more of an even heat, meaning no hot or cold spots. The twin size pad comes standard with one easy to read, easy to turn, non-slip computerized controller to adjust the temperature of the pad. With an automatic pre-heat and hold feature you simply turn it on and the pad will warm up on HI until it reaches the temperature that you preset your dial on and then adjusts itself to hold it there. For your safety and convenience it has an automatic shut off feature that will shut the pad off after 10 hours just in case you forget. It also comes standard with built in over-temperature protection for that extra bit of safety and peace of mind. A fitted skirt on the bottom pad keeps it anchored in place and eliminates shifting or bunching and promotes better sheet fit. The removable top heated pad has six Velcro strips that attach to the bottom pad and can be conveniently unhooked for washing or warm weather storage while leaving the bottom pad on the mattress for year round comfort and support. It can be put back on just as quickly. Not recommended for use with an electric adjustable bed, water bed or blowup air beds (Sleep number beds are OK). Features: -Two pads in one.-Removable heated pad on top and plush mattress pad with fitted skirt on bottom.-Both pads are completely machine washable and dryable without any pilling, shrinking or stretching.-Patented non-hazardous low voltage ''Safe and Warm'' technology is safer than others on the market.-Saves energy.-Sleep better in a cooler room.-No more bulky wires.-Ultra-thin wires inside the Soft Heat pads are almost impossible to feel.-No hot or cold spots.-Automatic pre-heat and temperature hold feature for convenience and built in over-temperature protection for safety and peace of mind.-Single / Double control automatically shuts off after 10 hours for convenience, safety and savings.-Fits up to an 18'' Mattress.-Machine wash and dry.-Hypoallergenic fiber fill.-UL listed.-Color: White.-SoftHeat collection.-Distressed: No.Dimensions: -15 - 18'' H x 39 - 72'' W x 75 - 84'' D, 5.2 lbs.