With layers of blended British wool and viscose, lustrous cashmere, luxurious silk, Yorkshire wool, crisp cooling Egyptian cotton, kapok, super soft alpaca, long stranded hair and home-grown flax. The Santorini has 27000 innovative springs; including 100% recyclable advanced Cortec™ Revolution pocket springs, dual layers of pressure relieving HD 4000 micro springs and contouring Microlution Airflow springs. With an in-house woven FR chemical free mattress cover and four rows of hand side stitching, this Seasonal Turn mattress has a warming wool winter side and cooling cotton summer side.