It is spacious enough for you to sling in a water bottle up to 940ml/32 oz, and use the paracord cinch to lock at the top. The front mesh pocket and a back zippered pocket give you that extra bit of storage to keep your essentials like your keys, phone, sunglasses... Use the daisy chain attachment points and attach an extra bike light, or use the Topo Designs Crux Key Clip to attach other small items
Whether you are using it as a bike bag or a everyday bag to keep your water bottle and essentials with you on a hike or walk, this Topo Designs Mountain Hydro Sling is everything you want it to be