Good quality ignition amplifier.
TCI control unit
TZH control unit.
Ignition control unit.
So many names for the same thing.
All it does is read the signal from the Hall sensor in the distributor and amplify it to a level that the ignition coil can use.
They often fail, sometimes they give warning they are going with misfires and the like.
They ain't cheap, so make sure yours is definitely faulty before you buy one as you can't send it back!
Remember we are a repair workshop as well as a webshop! we know what goes on in some garages and we ain't in the habit of sending out parts for people to try before they buy, especially with sensitive electronics.
If your not sure, don't buy, simple as.