The shapes of difficult extrusion could rely on. There are many complex shapes for window or door seal, whether sponge or solid to work. Rubber with metal or with textile or soft pvc with hand pvc are very common.
Extrusion covers widespread of different materials, which poly merie and elastomeric compound such as PVC, PE, TPR, TPE, Rubber (Silicone, Natural rubber, SBR, Neoprene, EPDM) and PU are manufacturing lines. Co-extrusion is the extrusion which different material are extruded at he sametime.