Canada Post Parcel Envelope Sizes : Useful Links
My Current items are pretty thin and can fit through the slot size limit for standard mail (i.e. what you would use to mail a letter or thin envelope).
Envelopes are not supported with Canada Post through Shopify.
post expedited parcel delivery standards, canada post prepaid envelope ...
Canada Post offers domestic prepaid envelopes in three different sizes, all of which have now been replaced by new Conformer mailers.
I checked the Canada Post website and it seems like something of this size and weight could fall under large envelope for a letter or document which would cost ...