See also the Address response object.

gateway.address.find("aCustomerId", "anAddressId", function (err, address) {

If the address or customer can't be found, it will return a notFoundError.

customerId required, String

A string value representing an existing customer in your Vault.

addressId required, String

The two-letter value for an address associated with a specific customer ID. The maximum number of addresses per customer is 50.