Regular inspections by the TÜV technical inspection board warrant that our quality assurance system to DIN ISO 9001:2015 is operative throughout the company. Its effectiveness is certified and the system is verified by annual review audits. As a result, the quality of our products is continuously monitored. On request, you will be sent a works inspection certificate or production test log issued by our independent test lab. The quality and grade of the materials supplied is documented in these certificates.