You have to look at the Titanium Chef to see what the connection looks like. The connection on the older "Chefs" was a groove 13 mm long and 5 mm wide. On newer units, it is a bayonet fitting with an outer diameter of 43 mm. The KAX643ME fits the newer units. If you have an older boss (like me), you need the adapter KAT001ME. This adapter is a rather badly formed aluminium casting which fits very wobbly in the boss, but does the job well. In any case, it survived the endurance test (grating 4 kg of quinces) without any problems. - Take a look at the picture of the KAT001ME, you can see both connections there, and the text is also informative.

By the way, today the KAX643ME costs 159.81 sFrs; I bought it (at Galaxus) last October for 87.90 !

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