Legal analysis: Guarantee contract and letter of guarantee are two different kinds of guarantee, but they are two different forms of guarantee, which complement each other. Among them, the guarantee contract is provided by a qualified enterprise or legal person, and the guarantee of the insurance company is provided by the bank.

Legal basis: Civil Code of People's Republic of China (PRC).

Article 681 A suretyship contract is a contract in which the surety and the creditor agree that the surety will perform the debt or assume the liability when the debtor fails to perform the due debt or the circumstances agreed by the parties occur.

Article 682 A suretyship contract is an accessory contract to the principal creditor's rights and debts contract. If the principal creditor's rights and debts contract is invalid, the guarantee contract is invalid, unless otherwise stipulated by law. If the debtor, guarantor and creditor are at fault after the guaranty contract is confirmed to be invalid, they shall bear corresponding civil liabilities according to their faults.