Aluminum material must use aluminum which is processed by oxide. Because the aluminum material which without any oxide process will be oxidation naturally and dull after storage for a period of time. That will effect the case beauty directly.
In fact, the most important part of the aluminum flight case is the wheel. There are many kinds of wheel. Such as PVC wheel, PU wheel and loading wheel. Besides the wheel could be divided into single bearing, double bearing, single brake, double brake. The prices of different kinds wheel are different. Some may be gotten in several yuan, some may be gotten in dozens of yuan. Quality of the wheel decide the normal transport of the aluminum flight case. Certainly you had better choose a right shockproof layer. There are EV glue and pearl cotton for shockproof. Density, hardness and thickness of these two materials has the effects of protection and shockproof.
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