Voice coil for the Audax ( Polydax USA) TW025A0 or TW025L0 tweeter that is 4 ohm.
These are easy to repair. Unfasten the mounting screws hold the front plate, remove the defective voice coil holder and replace with the new one! Replace the front plate, fasten the screws and you are as good as new.
These will also fit older Audax units from the “Spica” era, however, in order for the terminals to clear the metal parts on the magnet, you need to do some serious metal grinding. Try this only as a last resort of finding a fix for any old system using Audax tweeters.