The Backpacks

Backpack's grade and quality are mainly from the aspects to determine.
First, manship work. Every corner and pressure lines are all very neat, no lines and jumper off phenomenon, each needle embroidery is very elegant, this is a high technology standard.
Second, look at the package of materials, usually with a 1680D two-ply fabric is more upper-middle. The 600D Oxford cloth is more commonly used materials. Another canvas, 190T and 210-like materials are usually used for relatively simple tote type of shoulder bag.

Third, the shoulder bag on the back structure directly determines the use of backpacks and grade. High-end mountaineering and outdoor or military backpack, the back of the structure are more complex, at least six to do more than EPE or breathable EVA pad, and even aluminum frame. General is a shoulder bag back around EPE do 3MM breathable panels, the simplest type of tote bag shoulder bag in addition to the material itself, but there is no cushioning material.
In summary, shoulder bags and go mainly to leisure-loving best choice. Different grades of shoulder bags for different occasions, no class in this state.