WHO ARE WE ? SOTRA SEPEREF and DYKA have been part of Tessenderlo Group for almost 30 years, working in close collaboration and sharing the same values. Today, SOTRA SEPEREF becomes DYKA SAS, but apart from our name, nothing has changed and we will continue to promote these common values: PROFESSIONALISM With more than 1000 employees in Europe, including more than 200 in France on the production site in the North of France (Sainte Austreberthe - 62), DYKA relies on teams of women and men with multiple skills, to imagine, design, produce, sell, transport plastic piping systems developed to the highest quality standards.