“The undersigned (hereinafter called ‘Guarantor’) for and in consideration of the sum of Ten Dollars ($10.00) and other good and valuable considerations in hand paid to the Guarantor, the receipt and sufficiency of which is hereby acknowledged, and to induce (bank name) a national banking association with offices and banking quarters at (address), (hereinafter called ‘Bank’), at its option, at any time or from time to time to loan monies, with or without security to or for the account of (customer’s name) (hereinafter called ‘Borrower’), and at the special insistence and request of Bank, Guarantor hereby unconditionally guarantees the prompt payment at maturity of the following (hereinafter called the ‘Indebtedness’):”

What does it mean? If you sign this, you’re the fall guy if the borrower defaults.

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