I work in the motor trade and Corteco, whilst not being a ' Premium' ( ie , Well known) brand , is certainly up there as far as the quality of their components is concerned.
Having attended a trade talk by Gates, I was aware that there are fake parts in circulation that claim to be a torsional damper, but are in fact machined from one solid piece with 2 grooves machined with an O ring glued in the grooves , to give the impression that it a proper 2 part pulley. I have seen one cut in half to prove the point.
I was glad to see that the Corteco part, even though sold at a very reasonable price, appears in all respects to be identical with the original component.
As they say in the North ......." Proper Job".
So avoid very cheap UNBRANDED TVD pulleys, which are out there.They are quite likely FAKE.