??? Our CTC does Not have any Teflon-tubes in nozzles or anywhere in extruder assembly,
So, I don't understand what you are asking about?

I have seen some Guide-tubes, for other printers, that attach the heat-blocks to extruder assembly, with Teflon inserts.
But I have read that they cause problems, and tubes without Teflon are better.
Those are Not in nozzles.

Those nozzles, that I sent you the eBay link for, should fit.