**1. Errors**

     Code          | Description                                                         
    ---------------|---------------------------------------------------------------------
     0             | Invalid JSON body                                                   
     1             | Field validation error                                              
     2             | Parcel size (length and girth combined) is greater than maximum     
     3             | Declared value must be 0 only for documents                         
     4             | Destination address is invalid                                      
     7             | Ship To ZIP does not exist                                          
     8             | There is no such ship_to.state for ship_to.zip                      
     9             | Invalid carrier service for ship_to destination                      

**2. Warnings**

     Code          | Description                                                         
    ---------------|---------------------------------------------------------------------
      W1           | label zip differs from ship_to.zip
      W2           | label city differs from ship_to.city
      W3           | label state differs from ship_to.state
      W4           | USPS city (by zip) differs from ship_to.city
      W5           | USPS state (by zip) differs from ship_to.state
      W6           | UPS applied delivery area surcharge
      W7           | UPS applied remote area surcharge
      W8           | UPS applied additional handling surcharge (weight)
      W9           | UPS applied additional handling surcharge (dimensions)
      
**3. HAWB**

    Last 11 digits (letters are ignored) must be unique among all shipments.

    Your full HAWB          | HAWB sent to US CBP    | Result
    ------------------------|------------------------|---------
    543210987654321         | 10987654321            | OK
    54321098765432ABCD1     | 10987654321            | Rejected

    This would be an error. Even though the 2 full HAWBs are different, they are the same when converted to the values which are sent to US CBP.
    

**4. MAWB**

    The IATA and US Customs rules for IATA MAWB's require that all MAWB's have a three digit Airline prefix and then eight digits. Those eight digits are a seven digit serial number and a mod 7 (unweighted) check digit.
    Using the MAWB 180-62148741 as the example, the airline prefix is 180, the seven digit serial number is 6214874, and the check digit is a 1.
    To confirm that 1 is the correct mod 7 check digit, you can determine the check digit two different ways. Method one:
    1. Divide the seven digit serial number by `7`
               `6214874 / 7 = 887839.1428...`
    2. multiply first number after decimal by `7`
                `.1 x 7 = 0.7`
    3. round the result up, to determine the check digit
                `0.7` rounds up to `1`
                the check digit is `1` (if the result were a whole
                  number, then no rounding is required)
      and method two:
    1. Divide the non-check digits by `7`
               `6214874 / 7 = 887839.1428...`
    2. multiply the integer result by `7`
                `887839 x 7 = 6214873`
    3. The difference between the number you started with and the result
       of step 2 is the check digit:
               `6214874 - 6214873 = 1`
                the check digit is `1`
    These calculations confirm that `62148741` is a valid MAWB suffix, and as long as the `180-` prefix is the correct airline prefix, you know you have a valid MAWB.