No modification of any Loan Document, including any extension or amendment of a Loan Document or any waiver of a Default or Event of Default, shall be effective without the prior written agreement of Lender and each Obligor party to such Loan Document; provided , however , that only the consent of the parties to a Bank Product agreement shall be required for any modification of such agreement. Any waiver or consent granted by Lender shall be effective only if in writing, and only for the matter specified.