The quality of the liners and resins used is decisive for the rehabilitation result. For this reason, we place great value on quality assurance. All factors relevant to quality such as thickness, density, stretching performance, coating etc. are inspected before, during and after production. Even the resin and the resin-liner laminate are regularly tested in our test centre and the experimental facilities. The comparatively high effort is reflected in the extremely low returns rate, which is not only appreciated by the installers, but also by the contractors.