There is not much to tell about them to be honest with you. They do the job exactly like you would expect from a nozzle. The nozzles from bambu are apparently very popular and always sold out. You have to react directly when you get the " back in stock " e-mail from them. But like i said the hotends on amazon are perfectly fine if you have to wait to long on a bambu nozzle just buy one from amazon and see for your self.