This collapsible SoftFlask holds up to 300mL of fluid and is designed for easy use on the go. Its slim, contoured shape slides smoothly in and out of hydration pockets, making it ideal for running vests or waist packs. The flask features a compact 28mm cap that helps it lay flat against your body for a more comfortable fit. Equipped with a soft silicone bite valve. PVC & BPA free.