Special flexible stripwound hoses with corrugated profiles are mainly used in exhaust systems. These hoses are very sturdy and not sensitive to torsional motions. As a corollary of the stricter exhaust gas emission standard Tier4, gas-tight elements and systems, such as corrugated hose and bellows solutions, are used to an increasing degree. Insulated systems that permit the maximal permissible surface temperatures to be reduced and are optimally designed for the confined mounting scenarios are also in use. Flexible fluid and return lines are used in the vicinity of motors. These improve the operational reliability and reduce both emissions and fuel consumption.