Its main feature is the water storage bladder, which is trademarked as the “Osprey Hydraulics” system. The trademark is more than just a fancy name for a day pack with a reservoir. It’s designed to conform the reservoir to your back even when it’s full, so much so that you almost forget your carrying 6.5 pounds of water on your back when you rest against a rock or tree.
The reservoir is also designed well enough to warrant a trademark, which is dubbed the HydraForm. With a handle, it is built so that the bag slides in and out of the pack easily, even when it’s full of water, making cleaning and refilling a breeze.
Inside the reservoir, Osprey used the antimicrobial technology called AquaGuard (also trademarked). AquaGuard is a medical company known for using moisture barriers to protect surgical incisions from dangerous bacteria. The clever designers over at Osprey decided to use the same technology that keeps wounds clean to keep bacteria and mold out of your drinking pack. Genius.