In addition comes with the diffuser an acrid smell plasticizer, I've been able to get not even by 1 week in freezer (sometimes helps) and a few days in coffee beans. Absolutely useless, especially when one is working with people.
Only good is the seat of the Canon Speedlight 430EX, because I have nothing to complain about. For 15 euros is not worth the effort, the part to send back, I would not buy it again.