You can rely on the NALGENE All-Terrain Bottle wherever you go. It's great for carbohydrate/energy beverages, easy to use, & simple to clean. The ATB fits most waist packs & backpack pockets. The hinged Lexan mud-cap keeps the drinking spout clean, & the slim profile & textured grip give you firm handling in virtually all conditions. The wide neck opening easily accommodates ice cubes for chilled drinks, & the neck configuration works with most major water purifiers & filters.