AutoTransponder.com is responsible for shipping the order out in a timely fashion with either USPS or FedEx, whichever is selected by the customer at checkout. Once the order is sent out, it is up to the mail service to deliver the package on time. AutoTransponder.com cannot be held liable for lost packages or late delivery times caused by the delivery services. Tracking information is sent to the email address given on the invoice, if provided. Customer must contact USPS or FedEx with any problems or delays after the order is shipped.