The size is: 44 cm x 24 cm x 14 cm (17.32 inches x 9.44 inches x 5.5 inches); weight: 590 g.
There are 2 main compartments with zip and a helmet bag with adjustable straps. There is an inner sleeve inner pocket in the main compartment for your water bladder. You can cut the hole on the right side of the backpack through your hose.
Model: S2321
There are 2 side pockets designed for your water bottle and roof. The back straps padded with mesh material make you feel comfortable when you use it for some time.
The back part is made of mesh panel, which can be removed if you do not want it, you can also return it when you need it.
There is a helmet pocket on the front of the backpack, which can be used to store your helmet when you use it as a bicycle backpack. You can store some other things, do not use the helmet.