Twin xl fit my sleep number split king bed perfectly! Great to prewarm the bed on cold nights. This mattress pad warms up quickly and is nice & toasty. Medium firmness thick memory foam mattress with 3-inch bamboo fiber memory foam pad.

As for durability, yes! Worth the price, easy to figure out. A much needed improvement. Instructions are simple and easy to follow.

The plug is mounted on top of the sleeping surface. During the night, my ankle finds it and lays across it. It helps with keeping my back, buttocks and legs the most.

Left both cords unplugged overnight. Next day plugged both ends back into the wall outlet (not an extension cord) and flashes. Controller simply blinks.

The elements are fragile and leave wide swaths of your bed cold. This pad is also bulky after putting sheets on very wavy and bulky. I am tall enough to need the bottom of mattress for my feet and this hard and bulky electrical connection is exactly w...  Read More

Both controllers quit working after about one year. The page lists a 5-year warranty, but they don't respond to any inquiries. Lasted less than 3 months.