Keder consists of two parts: a core and fabric. The core is made from extruded PVC, or another elastic material, to allow flexibility. The core is then wrapped in Keder fabric, which has exposed fibers on the outside to allow the Keder to easily slide into an extrusion with a luff groove – keder track. It has coating on the inside, to ensure proper adhesion during welding. For maximum strength, there is a Double Coated Keder available.