A patent for this method of producing glass wool was first applied for in 1933. The original filter pads were made of glass wool. Plug with glass wool and install in the injector block. In Europe, mineral wool and glass wool are the main insulators in houses. Glass wool is acceptable as packing material instead of cotton wool. The name is a portmanteau of the Norwegian word "glassvatt", meaning glass wool. Glass wool used as insulation material is the company's main product. Glass wool is produced in rolls or in slabs, with different thermal and mechanical properties. In tests, glass wool was found to be highly resistant to the growth of mold. The most common modern-day material is glass wool, or wrappings of aluminium foil. Europe also includes glass wool which, together with ceramic fiber, are completely man-made fibers. In comparison, glass wool typically has an R-Value of only R-3 to R-4 per inch.