Basic Top Mattress: Pliable top mattress with a soft cotton-filled summer side, a New Zealand wool-filled winter side and natural latex in the middle. Luxurious year round comfort. Height 9 cm. (3.5″) Natural Latex mid-Mattress: Made with premium 100% Talalay latex, free of allergens and other harmful agents. Transverse Pocket Spring System: For unparalleled comfort, measuring 13 cm (5.1”) tall. Pocket Spring System: Heat treated piano wire pocket springs for contouring comfort that will last. Measuring 9 cm (3.6”) in height. Handcrafted Wooden Frame: Rest with a clear conscious knowing that the Koster is made entirely of premium hand-selected pine from Sweden’s sustainable forestry operations.