To convert your floor pump to the AIRPORT pump head, first loosen the union nut on the existing pump head and pull the pump head, together with the union nut, off the hose. (Note: If the old pump head cannot be removed, you can cut the hose directly behind the pump head. Please note that this will shorten the pump hose by a few centimetres.)
Next, loosen the union nut on the AIRPORT pump head and slide it onto the hose. If it does not fit over the hose, you can cut off the first section of the hose.
Then push the AIRPORT pump head firmly into the hose and tighten the union nut securely.
In this video, you can see step by step how to replace the pump head: