Added, sorry and thanks :)
- doesn't match the product description
- has different qualities from the model advertised or shown to the client
- is not fit for purpose - either its standard purpose or a specific purpose ordered by the customer which you accepted
- doesn't show the quality and performance normal in products of the same type
- wasn't installed correctly - either by you, or by the customer, due to shortcomings in the instructions
IF YOU INFORM your customer that the product you are going to sell has quality problems, they cannot then claim redress from you about this particular defect."<<<<<<<<<<<<<<<<<<<<<