Works perfectly to open the 50 and 100 mL vials of Botox. There may be cheaper ways to open vials, but when the vial costs as much as Botox does, I want to use the proper tool! This gets it done easily, and without worrying that I’m going to break the bottle in the process. I have seen other versions of this online which cost about twice the price, but are only single sided. This handles both sizes in one tool, for a good price, and I can’t imagine that the other tool could work any better than this. This tool feels very solid and well-made.