The elastic keeps the sheet in place on the mattress. Made from 100% cotton, a natural material that’s soft against your child’s skin and gets softer with every wash. Includes: 1 fitted sheet 100cm x 120cm and 1 fitted sheet 100cm x 150cm . Machine wash ,hot 140°F (60°C). Do not bleach. Tumble dry, normal. Iron, high temperature. Do not dry clean. Shrinkage 5%.