This is an enhanced version of the standard usps shipping extension. It allows for shipments over 70lbs and uses product sizes to determine box sizes. It does not use a packing algorithm, but uses a more simplistic volume calculation. It's not ideal, but is much better than having no size associated with shipments.

Features:
- Minimum and maximum shipping weights.
- Minimum and maximum volume (box size).
- Minimum shipping rate.
- Weight and volume adjustments to account for shipping box and packaging (fixed and percentage).
- Rate adjustment (fixed and percentage).
- Disables flat rate boxes if the calculated box is too large.



To Install: There are no modifications to existing files. Just copy the files in and setup the shipping method.


Notes:
- Only the gross shipping weight is displayed, not the dimensional weight
- The box size calculation is very simplistic. It calculates the total volume then assumes an approximately square box. However, it will not make any dimension of the box shorter than longest corresponding item dimension.
- Make sure you test it's function first when using flat rate boxes since the selection of flat rate boxes is dependent on the box size calculation.
- See the 'UPS Shipping - Alternate' extension for the UPS equivalent.


Version 0.4 fixes a non critical warning on the administration configuration page.
Version 0.5 fixes an issue causing the warning 'shipping method required'
Version 0.51 Fix for international shipping.
Version 0.60 Fixes an issue where it was not correctly calculating the total shipping for multiple boxes.

If you have issues, be sure to enable the debug mode and check the opencart log file. The query generated with box sizes and weights along with the response from USPS will be logged.