Small Hydration Pack / Water Bottle Replacement
Just wondering if anyone knows of any small non-backpack hydration packs/water container? Essentially I just want something that I can refill throughout the day and put in my pocket, not backpack-based. Just needs to hold 300-400 ml and be flexible. I usually take a plastic bottle of water but plastic bottles crush easily and are a bit of a pain so I'm looking for a better solution.