Ah...they're heated! When people realise this it usually raises an approving eyebrow. The word therapeutic is often banded about as an adjective to describe relaxation but the word really derives from the Latin 'therm' which literally means 'heat'. All our beds have a thermostatically controlled heater which can be adjusted for the season, your preference and most importantly, your comfort. Because our bodies need to be a certain temperature to function, the heater, set at the level you choose, helps you relax and so sleep better for it. It promotes blood circulation too and the whole bed is warm, not just the patch you lie on. (No fear of turning over onto the 'cold bit' anymore!)