Backpack

A backpack, which in the closed state, comprises:

• an under side, an upper side, a plurality of lateral surfaces, an elongate surface to be carried on the back and a front surface;
• and
• said backpack, including:
• a tub-shaped backpack body;
• an opening region formed on a surface which is formed with at least one fold-down flap;
• whereby a complete opening of said opening region of the tub-shaped backpack body is made on the elongated surface to be carried on the back and on the at least one fold-down flap by means of a zip closure having opposed zipper closure ends, and wherein the surface to be carried on the back is provided with a backpack carrying system with respective pairs of backpack straps hip belts with pairs of hip belt padding and pairs of back paddings spacing respective backpack straps and respective hip belts;
• respective ones of said pair of backpack straps, said pair of hip belts, said pair of hip belt paddings, and said pair of back paddings fixed on separate opposed sides of said elongate surface to be carried on the back and formed on opposing sides of said opening region of said tub-shaped backpack body and forming said backpack carrying system in said closed state;
• said at least one fold-down flap having at one of said opposed zipper closure ends of said zip closure and covering a portion of one of said plurality of lateral surfaces in said closed state;
• the elongate surface to be carried on the back in said closed state has a concave shape in the closed state;
• wherein said zip closure is one of a waterproof zip closure or a pressure-sealed zip closure;
• wherein each opposed upper region of the tub-shaped base body is directed toward the opening region and further comprises:
• opposed pairs of rigid reinforcing means fixed on an inner side of said tub-shaped backpack body proximate said zipper closure;
• opposed pairs of engaging reinforcing elements are arranged on respective rigid reinforcing means and engage into each other in a positive locking way when said backpack is in said closed state;
• opposed pairs of rod-shaped elements join and space respective pairs of said rigid reinforcing means, and each rod-shaped element extends parallel to the zip closure on either inner side of said opening region;
• and
• an inner tension device spaced on opposed inner sides of said opening region proximate said zip closure and engaging in tension when said backpack is in said closed state;
• and
• each said hip belt is fixed to said respective reinforcing means.