Package contains 50 black mask beads. These soft rubber beads can be added to existing or new facemasks to enable the wearer to adjust the size of the elastic. Easily threaded onto 1/4" elastic. Insert a threaded needle through the small hole and out through the larger hole. Loop the thread around your mask elastic and then thread the needle back through the large hole and out the small hole. You then can use the thread to gently pull the elastic into the bead and out the other side.