One would logically assume that with the name "Fein Turbo III" in the title, it might actually fit on the end of a Fein Turbo III vacuum hose. Sadly, this is not the case. It requires the soft rubber extension to fit as the end is the exact same diameter as the end of the hose. Likewise, the other end should fit to a 2-14" dust port but that to is a false expectation. It requires yet another adaptor to fit. All in all a great disappointment. $14 including shipping was a complete waste of money.