Dear The [product] which you sent us for repair has been modified in the following manner: [specify] . This modification is a violation of the terms of our warranty. I am forwarding a copy of our written warranty in case you have misplaced yours. You will note that the warranty does not cover "A defect caused by the modification or repair other than through [specify] or its Authorized Agent." We will make the necessary repair for you, if you wish, at our flat charge rate of $ . We have enclosed a card for your convenience with pre-printed instructions. Simply check off the appropriate box and we will act accordingly. We must ask that you remit the cost for repairs with your instructions, if you would like us to service the product. I trust you will understand why we are unable to provide this service free to you at this time. Thank you for purchasing one of [name of firm's] products. We hope that we can be of service to you in the near future.