This German manufacturer is known for its inexpensive but decent quality rucksacks and has been making bike bags for a few years now, including some very functional waterproof panniers in conjunction with Ortleib.
The two packs differ in size and number of compartments, but share the same main feature, a pair of raised ridges that sit against your back to help you keep cool. Deuter calls these 'Airstripes', and each one is made up of rounded foam blocks overlaid with mesh, so that there's room for air to flow through the ridges themselves as well as between them.
The Hydro 2.5 has a large outer pocket, plus a pleated 'floating' pocket held in place with an elastic cord that also provides a place to carry your helmet off the bike or a bulky weatherproof item like a jacket. The 1.5 has one medium-sized, flat outer pocket.
Two bladders are available, in 1.5 litre and 2.5 litre sizes, but both packs will take the larger bladder, and there are Velcro loops inside them to hold the bladder up as it empties. The 2.5 litre bladders actually hold 2.6 litres if you fill them carefully.
On the trail
We found the compartments on the Hydro 2.5 easily swallowed a typical stash of ride junk: tubes, tools, mini-pump and food. On your back, it's a very comfortable and stable pack, which is helped by the broad shoulder straps and the sternum straps, plus the elastic holding everything snug in back.
The Airstripes seem to do what they're intended to. My shirt was substantially less soggy at the end of a three hour ride on a warm day than with my usual water pack and the mesh straps also noticeably increase ventilation at the shoulders.
Long zips make the pockets easy to get into when you need your stuff, but the outer pocket uses a vertically aligned zip, and that's a bit of a worry; leave it open and things fall out. It's also the zip most likely to get muddy, so it's good to see a cover to protect it against the ingress of crud.
This is a very comfortable and practical pack, especially in hot conditions when the Airstripes really come into their own. A higher-flow mouthpiece and better placement of the outer pocket zip would be improvements, but neither is a show-stopper.
Pro: Comfortable, stable and well-ventilated water pack
What do you think of the Hydro 2.5 or any other water pack? Let us know
November 2 tech features, news and letters
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