It is important to be able to set limits on the dimensions that your carriers will support.  The following Prestashop 1.5 tutorial will instruct you on how to set the maximum width that can be shipped by your carrier.

How to set the maxium width accepted by a carrier in Prestashop 1.5

1. Go to the login for Prestashop 1.5 Administration Panel and login as an Administrator
   
2. Hover over SHIPPING, then click CARRIERS from the drop-down menu when it appears.
3. Create a new carrier option by clicking on the ADD NEW button.   Or, select the shipper that you need to modify, and click on EDIT to make changes
4. Go to the CARRIERS section and scroll to MAXIMUM PACKAGE WIDTH as per the screenshot below:

   

5. As per the note below the blank, you can leave the field blank by setting it to zero.  The carrier will not use this dimension if it is set to zero.
6. Click in the field to set the max package height.
7. Click on the SAVE button in the top right hand corner

Setting the dimensions for the out-of-range behaviors is important because it allows you to limit the package size supported by your carriers.  Make sure to set these values in order to prevent confusion between your customers and shipper.