Custom fields in Braintree

Custom fields in Braintree
custom_fields field
Tax ID (only for customers)
Customer’s IP Address (only for customers)
Description of the transaction (only for one-off transactions)
Code for the evidence country in standard format: ISO 3166-1 alpha-2 (ES, FR, US, GB, etc.)
Brief description (max 255 characters) of the evidence. Required field for additional evidence.
Unique code of the product or service sold.