What are the domain's extended attributes?

Certain country-code TLDs such as .CA, .COM.AU, .COM.ES, .ES, .FR, .NOM.ES , .NET.AU, .NU, .ORG.AU, .ORG.ES, .SG, .UK, .US, generic TLDs like .XXX and .NYC require that you provide some additional information while registering domains.

This mandatory additional information is called extended attributes. These attributes can be specified explicitly during the checkout (you need to use standard Checkout instead of Express Checkout).

NOTE: Extended attributes for .UK and .XXX domains are optional, however, .XXX domains without extended attributes won’t work correctly.