The necessity of iron, believes that many seen double open box or a few more high-end packaging customization design will be found, the vast majority, there will be a magnet this accessories, of course, the heavens and the earth cover heaven and earth and surrounding edge cover is an exception of type box, then why the magnet is widely used on these high-end packaging cartons, actually very simple, Double open the packing box can have a common, is the box itself if only depend on the inside and outside the box or a box pasting friction stuck to each other, to ensure that the box in a closed state, very, very difficult, because of the characteristics of double open, will let the box of the contact area is not like ordinary even picked up a vertical outer cartons, the inside of the box will not fall out, in order to ensure that the use of time, Double open box in the open when the fluency is not blocked, will be relatively wide, wide will bring a more difficult to rely on the box itself to overcome the difficulties, double open box is not tight
