# Note 1.2. Pro-Rate Order. Select API

1. Here is the list of exchanges available in the Pro-Rate Order window. The exchanges with added API keys are colored in white. Click on the name of the exchange to expand the list of added API keys of this exchange.
2. The list of the connected API keys. The Default API key is the main key of the exchange. When you switch exchanges in other terminal windows, this API key will be used by default as the first and main key. You can change the default API key in the "My API Keys window"
3. The API key with a checkmark in the CheckBox is the active API key for the Pro-Rate Order window. By default, for a Pro-Rate Order, all available API keys, on which the selected currency pair is available for trading, will be automatically enabled (checked). Eligible accounts will participate in the Pro-Rate Order Size distribution. If you want to exclude an exchange account (API key) from the Pro-Rate Order Basket list, then uncheck the boxes next to such an API key. Pro-Rate Orders will be proportionally distributed among the enabled (checked) exchange accounts (API keys).