The Salt Therapy Boards are made of fine rock salt granule originated from one of Europe's most famous salt mines used for curative purposes. The same salt is used for our very popular breathing salt therapy inhaler, the Saltpipe. The humidity of the air of your home absorbs small particles of salt from the large surfaces of the Salt Boards, which makes the air of the room slightly salty. The air of your home becomes a bit similar to the air of the salt mines used for curative purposes. This slightly salty air has many health benefits starting from cleansing your respiratory system to overall psychical conditions.