Meta Key Description Data Type _product_type Product type: "traditional" or "digital". Defaults to traditional. String _product_price Product price in base currency Float/Numeric string _product_tax_ids Array of tax rate IDs applied to product Array of integers/strings _product_company_index Index of merchant company assigned to product (0 = default/first company) Integer _product_invoice_description Description shown on generated invoices (separate from post content) String (text) _product_internal_notes Staff-only notes not shown to customers String (text) _product_clients Array of Portal client post IDs with access to this product (empty = all clients) Array of integers _digital_product_file_path Path to digital file stored on external server String _digital_product_file_name Original