Not sure if this belongs here or else ware. But I’m after a 2l or so hydration back pack. Something that’s insulated as well. No storage is required. Unless it’s space for frozen ice packs ect. I often spend 8hrs at my block shooting or a day at the gun range. It’s all great in the morning but by 12 might as well drink water straight from the kettle. Also one of my comps we walk through the scrub hence the back pack. As I’ve had a gastric sleeve I can’t really gulp down water. So just try to sip away at it. Also can you throw the bladders in the freezer? Or am I just best filling with ice cubes and then filling with cold water.