The difference between an improperly and properly packaged iMac computer is ensuring the computer is sitting flush with the bottom corners of the packaging.
Improperly Seated
This image shows an iMac which is not fully seated in the packaging. Notice the iMac corner is not flush with the Styrofoam. See Figure 1.
Figure 1 Improperly seated iMac
Properly seated
When repacking an iMac using the original packaging material, ensure the front bottom corners are fully seated to avoid damage during shipping or transport. See Figure 2.
Figure 2 Properly seated iMac
Improperly Seated
This image shows an iMac which is not fully seated in the packaging. Notice the iMac corner is not flush with the Styrofoam. See Figure 1.
Figure 1 Improperly seated iMac
Properly seated
When repacking an iMac using the original packaging material, ensure the front bottom corners are fully seated to avoid damage during shipping or transport. See Figure 2.
Figure 2 Properly seated iMac