Style, comfort, and functionality come together beautifully with the aden + anais 100% cotton muslin fitted crib sheet. Wonderfully soft and the ultimate in breathability, cotton muslin is the ideal fabric to keep baby warm in winter and cool in summer. Breathable: open-weave allows liberal airflow. Year-round comfort: warm in winter, cool in summer. Tailored fit: fits standard crib mattress up to 52 in x 28 in x 8 in. Machine washable: softer with every wash. Coordinates nicely with aden + anais Dream Blankets, Cozy Sleeping Bags, Swaddle Blankets, and Changing Pad Covers. Wash before use. Cold water wash with like colors; tumble dry on low heat. Do not add bleach; do not iron.