| Name | Type | Description | Notes |
|---|---|---|---|
| type | string | The type of the shipping upgrade. Domestic (0) or international (1). | |
| upgrade_name | string | Name for the shipping upgrade shown to shoppers at checkout, e.g. USPS Priority. | |
| price | float | Additional cost of adding the shipping upgrade. | |
| secondary_price | float | Additional cost of adding the shipping upgrade for each additional item. | |
| shipping_carrier_id | int | The unique ID of a supported shipping carrier, which is used to calculate an Estimated Delivery Date. Required with `mail_class` if `min_delivery_days` and `max_delivery_days` are null. | [optional] [default to 0] |
| mail_class | string | The unique ID string of a shipping carrier's mail class, which is used to calculate an estimated delivery date. Required with `shipping_carrier_id` if `min_delivery_days` and `max_delivery_days` are null. | [optional] |
| min_delivery_days | int | The minimum number of business days a buyer can expect to wait to receive their purchased item once it has shipped. Required with `max_delivery_days` if `mail_class` is null. | [optional] |
| max_delivery_days | int | The maximum number of business days a buyer can expect to wait to receive their purchased item once it has shipped. Required with `min_delivery_days` if `mail_class` is null. | [optional] |