Good elasticity stretches freely, and will not deform after repeated use. The silicone material is odorless, non-toxic, skin-friendly, safe to use, and provides excellent protection while swimming. Neutral Short/Long Hair: The swimming cap has good stretch and space, with enough stretch to fit most head shapes, including men, women, boys, girls, adults, children, and children, whether it is Short or long hair. It conditions and protects your hair from chlorine, and salt water, and keeps your hair safe and tangle-free while swimming Upgraded Ear Protection Maximizes protection against water entering the nasal cavity and ear canal, preventing bacterial and fungal infections. We've also lengthened the swim cap that partially covers the ears for an extra layer of protection that helps keep the earbuds in place so you can focus on swimming. Perfect Ergonomic