A sound damping device for a tubular duct, particularly a gas transporting tract of an internal combustion engine having a least one bypass channel running parallel to a main duct in a section of the duct. Voltage terminals of the SATA control chip, the USB control chip, and the storage chip are connected to the first pin of the connector. Thereafter, the old tunnel is deleted from the old LTE anchor. The generators can be of permanent magnets or variable reluctance, non-watertight and optionally independent. The inner tube is slidably insertable through the outer tube until the balloon is situated within a bore formed through the gas flow duct and is inflatable therein to block any gas leak through the gas flow duct.