Once upon a time, all ponytail holders had a little metal clamp that held the two ends of the elastic together. Now there are metal-free versions of the ponytail holder that are either a continuous loop of silicone or a fabric elastic held together with glue. Stop using the metal elastics! They cause damage to the hair -- frequent ponytail wearers will often see a line of broken hair where the metal ponytail holder usually hits. They also tend to get caught in hair and rip it out when the elastic is removed. Stick to the metal-free varieties.