As with all of our beds, the base is made out of Swedish slow growing pine wood. On top of the base, a mattress with two sets of tempered steel pocket springs that combined with layers of cotton, wool and horsehair. Delivers comfort in the way only a Mattsons can. The Pure has a responsive, steady support and creates a feeling like no other. The Pure is also available as Pure ST, with two rows of hand stitching to firm up the side panels of the mattress for additional stability, comfort and great looks.