Co extrusion involves combining two or more extruders to produce tubing with two or more materials. The most common application of the co-extruded process is in the production of tubing with Radiopaque stripes visible under X-ray. Stripes containing a filler visible under x-ray can be encapsulated within the wall of the tubing. Typical fillers include Barium Sulphate, Bismuth Trioxide, Bismuth Subcarbonate and Tungsten which can be used in various concentrations to enhance radiopacity.

Co extruded tubing can combine materials with different but complementing properties (durometer, colour, opacity, radiopacity, tensile strength) to provide custom catheter solutions.

A specific area of competency within co extrusion is the production of multi-layer tubing.