The Direct ACH Payment only requires the Payee’s bank routing and account numbers in order to initiate the transfer.
Your payment activity will also be available to see on the Payments tab and Transactions tab. To see a payment's details, click the “Manage” dropdown on the payment transaction. From there, you can choose to send another payment or cancel the pending payment as long as you are within the 2 hour cancelation window.
See Also: Cancel a Payment