Hydration That Moves With You. The KitFox 500ml Soft Flask is the lightweight, durable solution for runners who need reliable hydration without the bulk. Engineered for the demands of the trail, this flask collapses as you drink, eliminating the "sloshing" sound and feel of traditional bottles. Whether you're navigating a technical mountain ultra or a humid summer road run, the high-flow bite valve ensures you get the hydration you need with zero effort. The wide 42mm opening is a game-changer for race days—allowing for lightning-fast refills and the easy addition of ice or electrolyte tablets. Available in three fun, bold colours, these flasks don't just perform—they stand out. Match them to your kit or use different colours to distinguish between water and your fuel mix at a glance. Capacity: 500ml (17 fl oz). Weight: Ultra-lightweight (approx. 35g when empty). Material: 100% BPA and PVC-free TPU; taste-free and recyclable. Cap Size: 42mm wide-mouth opening. Care Instructions: Top-shelf dishwasher safe. Pro Tip: Store in the freezer between runs to keep it fresh and bacteria-free!