Warranty Certificate The Manufacturer guarantees normal work of D-421 during 12 months from the date of purchase provided that all service regulations and the rules of storage given in this manual were kept. The guarantee repair of the faulty device can be carried out on presentation of: the buyer's check, confirming the fact of the purchase; the correctly filled guarantee coupon; the certificate(act) of a technical condition of D-421 produced by the authorized service centre. The exchange of the faulty device for a new one can be fulfilled only. The guarantee is not valid for the device: with the broken seal (deleted nameplate); with the mechanical, electric and other damages caused by its improper operation or nature disaster; with presence the strange objects (liquids, insects) inside of the device. This Guarantee is not valid for any devices, connected to D-421. In case of any malfunction of D-421 through the fault of the manufacturer during the guarantee period, please, address our service-center: 105120 Moscow, N. Syromyatnicheskaya Str. 5/7