What Our Gearhead(R) Experts Are Saying: "I switched to the Zulo for fat biking and instantly noticed the comfort difference. No sweaty back and no sloshing, and the insulated hose means I'm not dealing with frozen valves anymore. It fits snug and carries just enough gear without overloading."When we're hammering through winter trails on the bike or training in sub-freezing temps, the USWE Zulo 6L Winter Hydration Waist Pack keeps hydration accessible and gear dialed without the weight of a full pack. Built specifically for cold-weather action, this ergonomic belt system is shaped for a snug, bounce-free fit that doesn't interfere with motion or layering. The included 1. 5L Compact Lumbar bladder uses an insulated drink tube with a magnetic clip to keep fluids flowing even in freezing conditions. Inside the pack, we've got a smartly laid out main compartment for tools and layers, a multi-pocket organizer, and quick-stash side pockets for snacks and gels. A built-in bike light attachment adds visibility for short winter days, while the updated foam ridges along the back improve ventilation and stability during high-output rides.