The last thing a company associated with ocean and sea freight would like to find out at an international border is that they don’t have the proper documentation to move their goods. USPS also provides express shipping for international shipments. Here are the shipping options for USPS international shipments: https://canadashippingcompanies43210.creacionblog.com/27858570/helping-the-others-realize-the-advantages-of-cheapest-shipping-from-canada-to-us