In non-recourse factoring, the factor takes on part of your customers' credit risk. If an approved customer goes out of business or cannot pay because of insolvency, the factor absorbs the loss instead of charging it back to you.
The protection is narrower than the name suggests. It usually covers only a customer's financial inability to pay. Disputes over the work, short payments, returns and slow payment generally stay with you, and coverage may apply only to customers the factor approved in advance.
That protection has a price. Expect a higher fee or a lower advance rate than with recourse factoring, and check the contract's exact definition of a covered loss before you sign.