What Our Gearhead(R) Experts Are Saying:"I like this size when I know the run will stretch a little longer. The grip-free strap keeps my hand relaxed instead of squeezing a bottle, and the soft flask compresses as I drink, so it never feels bulky. The small stash pocket is also handy for a gel and my key during marathon training runs."Longer miles call for hydration that stays comfortable in our hand from the first stride to the final stretch. The Pinnacle 18oz Soft Flask from Nathan Sports gives us more water without adding unnecessary bulk, making it a dependable companion for marathon training runs, trail sessions, and steady endurance miles. The soft flask compresses as we drink, keeping the load compact and minimizing slosh along the way. Nathan's ExoSpine structure provides stability and support so the bottle maintains its shape while still collapsing naturally as the fluid level drops. A breathable mesh strap contours to our hand for a relaxed, grip-free carry, and the expandable wraparound pocket stores a gel or keys so we can head out the door with just the essentials.