Today, different systems are applied regarding the replacement of asbestos for the sealing of engines. Nonasbestos beater addition facings are used in addition to expanded graphite.With the material HDC, new systems have been applied in the process of replacing asbestos. The design of this material as well as its characteristics are described in this paper. The significant differences of HDC as compared to other nonasbestos systems will be explained. Not only laboratory results, but also results of engine tests will be cited. The latter results have been obtained in the course of testing on modern engines.