The slider for the window regulator - BMW part number 5133 2 290 479 - has not been available for several years. It is "not so unimportant" for the smooth running of the windows. Designed as a wearing part in the window rail, it has now reached the end of its service life after almost 30 years. We have redeveloped the sliding piece based on hand sketches, original parts, etc. (creation of a 3D drawing in Catia, construction of injection molds, definition of tolerances, production of the pre-series (first out of tool), trial assembly, measurement and quality assurance, series production. Position 05 of the door sketch