The Nike Slim Waistpack 4.0 New is a lightweight and functional waist pack, perfect for running and everyday activities. Nike Dri-FIT technology helps keep you dry and comfortable, while an elastic waistband allows for a custom fit. A practical stretch pocket stores your essentials, and a reflective Swoosh enhances visibility in low light. Nike Dri-FIT helps keep you dry and comfortable while you move. An elastic waistband provides a comfortable fit. Lightweight, body-hugging construction. Stretch pocket stores small items. Reflective Swoosh enhances visibility. Material: 90% polyester, 10% spandex.