Looking for a big enough backpack

1, large size, wider, weight is heavier, 2, the posture backpack filled the barycenter apparently relatively high, in harsh terrain more difficult to maintain the balance, especially in rock climbing or drill muliensis cemetery geared, 3, head activity space is limited; 4 and coiled-wire systems are not in accordance with the ergonomics design, bear is not comfortable. Inside the bag bag: pose a

Looking for a big enough backpack to hold all the necessary equipment, but also to small enough to comfortably daily use carry.

 Remember! No matter what a big bag, the user would normally have will play the full tendency, backpack unless really needs, otherwise you can to avoid extra large bag, the usual size classification in Europe, Asia, the backpack size capacity can accommodate more than by what the number (liter) volume liter for calculating unit:

55 to 80 litres: wide use type big backpacks, used for intermediate longitudinal walk; alpine mountains, 80 litres above: expedition type big backpack, long days alpine walk, overseas longitudinal expedition.