Refuture materials such as the well-known bitumen mats can be recognized by the composition, bitumen or butyl rubber, weight and self-adhesiveness, because detangunig mats are always self-adhesive. The principle of de-drumming mainly occurs with steel surfaces in, for example, ship and yacht construction, vehicles and mechanical engineering. But also thin, or actually light, vlkanne of aluminum, plastic and plyester can be de-drummed (mass-provided). The best-known form of de-drumming can be found under a steel sink, that black slice. De-drumming is a form of isolation in which a surface is held, as it were, so that no gong sound is possible anymore, for example in car doors. The best result is achieved when the subsoil of mass can be doubled.