If the product is found to be defective in material or workmanship, or if the product does not perform as warranted above during the warranty period, Thinka will either repair it, replace it, or refund the purchase price, at its option, upon receipt of Thinka for KNX, with proof of the date of purchase and an explanation of the defect or error. The repair, replacement, or refund that is provided for above shall be the full extent of Thinka’s liability with respect to Thinka for KNX.