Static mixer, a kit of parts and use of a static mixer

A static mixer for mixing together at least two components comprising:

• an injection molded or dimensionally stable mixer housing;
• a mixing inset arranged at least partly in the mixer housing;
• the mixing inset comprising a plurality of mixing elements which are connected by at least one peripheral web;
• and
• a sealing element,
• a passage between the mixer housing and the at least one peripheral web being blocked by the sealing element, and
• the sealing element being located in a middle section of a set of mixing elements, being a protrusion on an outside of the at least one peripheral web and being flexible and deflected by more than 45 degrees when the mixing inset is in an assembled state in the mixer housing, being oriented at an angle of more than 60 degrees to a line parallel to a mixer axis and in a plane of the at least one peripheral web, and having a length and a width and a ratio of the length to the width is at least 5:1.