An override field that a merchant can pass in to set the challenge window size to display to the end cardholder. The ACS will reply with content that is formatted appropriately to this window size to allow for the best user experience. The sizes are width x height in pixels of the window displayed in the cardholder browser window.
enum ThreeDSecureAuthenticationAcsWindowSize {
FULL_PAGE
W250_H400
W390_H400
W500_H600
W600_H400
}