Here’s what consumers have asked with answers from National staff and previous consumers.
National's return policy is listed at the bottom of their Home page under Easy Returns. The policy states you have up to 180 days to return an item. It states you can use the same shipping envelope to return products by turning it inside out. Using their Easy Return Label will cost you $6.95 deducted from whatever you paid for the item. If you want an exchange you will also pay to have the exchange shipped to you. They list standard shipping as $5.95, probably via USPS. I have not yet bought from this company, but was checking out their ratings and saw this question.