Adult headbands. The green headband has a 1 inch elastic in the back for stretchy yet once it's placed in your hair it stays in place. So no sliding down during the day for this headband. The knot headbands have an adjustable knot in front. Pull knot to make the headband longer on the sides or make knot bigger to make the headband tighter. These headbands are made of cotton and a few soft super stretchy fabric.