If you have a check of this bank, you can get the account number and check routing number at the bottom. Here is a picture to show the information http://usbankfound.com/check-routing-num... it may be more intuitive for you to take a look at it.
Definition of retainer 1: the act of a client by which the services of a lawyer, counselor, or adviser are engaged 2: a fee paid to a lawyer or professional adviser for advice or services or for a claim on services when needed
A retainer is usually used to hold the teeth in place. Orthodontists use retainers of different types to maintain correction after treatment. Sometimes retainers can be used for treatment, in certain cases where only limited correction is needed.