Just received X-pole xpert - xjoint 180mm missing?

Hoping someone will be able to help. Just opened my X-pole Xpert package but when I go through the list of what should have been delivered, I think 1 piece is missing but I don;t know if it's just be being retarded.  I have the A and B pole, the micro base, the dome, top adapter, 2 extensions but only 1 xjoint (measuring 200mm) For my ceiling which is 2435, I should be using the shortest extension and the 180mm xjoint. That of course is the piece I can't seem to find.  Am I going mad and the 200mm magically turns into the 180mm somehow in a way I don't understand?  Thanks! Li Marie