Osprey Hydraulics 500 ml Soft Flask is a lightweight and collapsible soft flask designed for running and fast-paced hiking. With a volume of 500 ml and a weight of approximately 40 g, it is almost imperceptible to carry. When empty, the flask can be folded flat to take up minimal space.

The narrow, tapered shape is designed to fit the chest pockets of running vests and pack vests. The flask is made from durable, BPA-free and odour-resistant TPU with RF-welded seams. The high-flow drink valve makes it easy to drink on the move, while the wide opening simplifies filling, cleaning and the addition of electrolytes or ice.

The removable WingStay stabiliser maintains the flask's shape and prevents it from bouncing, even when empty. The flask is dishwasher safe and compatible with the UltraFlask Filter Cap (sold separately).