Corona Clay Company is a family owned and operated business since 1948 incorporated 10 years later. We here at Corona Clay Company guarantee our product 100. In our over 50 years of business we have not had any complaints that we were not able to rectify most due to improper installation. If there is ever an issue that needs to be addressed please feel free to contact my secretary Rose Villasenor. We want you to be 100 satisfied with our product and remain business associates. We appreciate your business and would be happy to provide you with a list of our satisfied customers upon request.