We guarantee each system, equipment or element designed by us, against fails due to a defective design. In the event we commit an error with respect to, or incorrectly perform the engineering services, we shall use commercially reasonable efforts to correct such error, or re-perform such engineering services at no cost to customer. Customers acknowledge it sole and exclusive remedy, and our sole and exclusive liability. For any defect or error in the engineering services shall be correction, re-performance or substitution of such services by us.