[. . . ] About HELIX Since its introduction in 1997 the HELIX brand sets new standards for sound excellence, technology and quality in the development and production of loudspeakers and amplifiers. the exploration of new circuitry concepts and materials, and guarantees that every HELIX customer owns a first class state-of-the-art product. [. . . ] If you choose to perform your own installation read the following information and precautions carefully. Failure to follow the stated precautions may result in personal injury and/or damage the audio system or vehicle. Mounting panel reinforcement may be necessary in some cases in order to prevent surface flex. This can be achieved by mounting the speaker on a metal or wooden sub-baffle behind the body or door panel. Unless you are replacing existing speakers of same size, mounting locations will have to be cut into the doors, body panels, or rear deck. In some cases speaker mounting holes will be precut in the doors, body panels, or rear deck steel. IMPORTANT: Never cut any metal that is an integral part of an automobile's safety or structural supportsystem. HELIX strongly recommends that you operate the complete audio system at low volume before final installation of your HELIX PRECISION automotive loudspeakers. This will allow a trial listening test before securing the loudspeakers into their mounting locations. 7 english CAUTION: Make sure that all speaker wiring is fully protected from cutting or wear. Any short circuits developing as a result could severely damage the radio/cassette unit or amplifier. Make sure that all speaker wires easily reach the speaker terminals with stress on the wire or connectors. Securing the loudspeaker Once you have tested the complete speaker system and have confirmed correct operation, turn the audio system off and prepare the loudspeaker for final mounting. [. . . ] c) Defects caused by incorrect installation or connection, by operation errors, by overloading or by external force. d) Products which have been repaired incorrectly or modified or where the product has been opened by other persons than us. [. . . ]