Now you and your partner can stop arguing over the nighttime thermostat setting. With the Navien Mate Bed Warmer, you each set a temperature for your side of the bed. So you both can decide which temperature you want your mattress pad at for the night. This mattress topper uses energy-efficient technology to keep you warm throughout the night. In the same way you would with a diffuser, you fill this bed warming topper device with water. It’s connected to the mattress warmer, and it warms it up with the heated steam. Available in three models, each Navien Mate warmer has a child lock for safety. Plus, every model allows you to set a timer: two models offer 12-hour timers and the third offers a nine-hour timer. This slim pad won’t take away from the comfort of your mattress, but it ensures you sleep warm and cozy all winter long.