The Cavendish Natural FirmThe firmest of our three Natural mattresses. Heritage construction, the deepest support layer we build below the flagship. Natural mattresses use wool, cotton, silk, cashgora and horsehair as the comfort layer rather than foam or latex. The reason is breathability. Natural fibres regulate temperature far better than synthetic fills, wick moisture, and have the lived in feel that's been used in proper British bedmaking for generations. The Cavendish