Fiber block is an anti-bacterial fiber. It prevents allergen producing dust mites from living in the mattress by removing their food source. Fiber block is washable material. You can rinse it and in 30min. use again. Filling is good for the air circulation and child's breathing. Fiber block keeps baby from an overheating. Quilted (sintepon) cover - 100% cotton which can be washed at 60°C. Thickness: 60 x 120 cm - 5 cm, 70x140 - 8 cm. Select the appropriate size!