You can send attachments up to 10 MB from Seller Central for specific contact reasons. If you use your own e-mail service (for example, Outlook), the 10 MB limit is for e-mail text and any attachments combined.
You can send one or more attachments (up to 10 MB) in your replies to a buyer’s message. Buyers can send one or more attachments (up to 10 MB).
The following formats are supported: