I tested a larger item and got this???????????????????

USPS Debug Mode Enabled!

weight: +lb, dimensions: regular
Setting dimensions: l=12 w=12 h=12 for Weight: 10
Weight/Dimension Filtering Enabled.
Removed 'Priority Mail Large Flat Rate Box'
Removed 'Priority Mail Large Flat Rate Box'
Removed 'Priority Mail Medium Flat Rate Box'
Removed 'Priority Mail Medium Flat Rate Box'
Removed 'Priority Mail Small Flat Rate Box'
Removed 'Priority Mail Padded Flat Rate Envelope'
Added Insurance, cost:2.30 to Priority Mail
Error returned for a package:
SimpleXMLElement Object
(
[@attributes] => Array
(
[ID] => 1
)

[Error] => SimpleXMLElement Object
(
[Number] => -2147219434
[Source] => DomesticRatesV4;clsRateV4.ValidateWeight;RateEngineV4.ProcessRequest
[Description] => First Class mail must weigh 13 ounces or less.
[HelpFile] => SimpleXMLElement Object
(
)

[HelpContext] => 1000440
)

)

USPS Debug Mode Enabled!

weight: +lb, dimensions: regular
Setting dimensions: l=12 w=12 h=12 for Weight: 10
Weight/Dimension Filtering Enabled.
Added Insurance, cost:2.30 to Priority Mail