This is James from S Korea and I saw your inquiry on ec21.site ..
We are manufacture potable Ondol is a Korean under-floor cooling and heating system. Hot and Cool Water Circulation Mat. MK provides neither drive noise and nor vibration as it has no motor pump for hot water and PCM cool pad. It provides excellent performance with high efficiency and ultra low noise (10dB or less) helping you to have good sleep. No need any more electric fan / air conditioner, No vibration, No noise, High Quality. Hot and cool water circulation mat is very good for your health!
Enjoy the sound sleep without any sticky feeling from the best temperature especially in the bed before getting to sleep/during your sleep.
I look forward to hearing from you.
James Do (Mr.) Assistant Engineer
MK Energy System
#226 Twin ville, 339, Seoul ,S Korea