Abstract: A tool holder including a tool box with a tool seat in a holding projection for receiving a tool in such a manner that it can be replaced. The tool seat is configured as a bore and has a tool insertion opening. The tool holder has a fastening side with a fastening projection and, facing away from said fastening side, an exterior, and during use of the tool centrifugal forces are effective in the direction from the fastening side to the exterior. This invention ensures the free rotatability of a tool inserted in the tool holder even if overburden material enters the tool seat. For this purpose, the holding projection has an opening penetrating the inner wall of the tool seat and creating a spatial connection to the exterior, and the opening opens the tool seat towards the exterior.