Will the stoppers fit all bottles?

It is impossible to have one stopper that will fit 100% of bottles. With the original tapered style the small o-ring fits very few bottles maybe some olive oil bottles. The middle o-ring fits almost all wine bottles and some with screw tops. The top o-ring fits some screw top bottles. The SS-9000 stainless cork will fit the majority of bottles and will have a tighter seal because in most bottles, 2 o-rings will seal and the o-rings are a different derometer of nitrile thus making them squishier (new technical term!).   The 9000 and 3000 fit the majority of wine bottles and a lot of whiskey/liquor bottles as they have the same screw top size.  The 4000 Cosmopolitan Whiskey stoppers (5 o-rings) fits whiskey, Bourbon, etc. usually top-shelf brands.  A lot of Bourbon companies have their own bottles made, making the variety of neck sizes a wide variable.   Photo shows the superior seal of the 9000, 3000 and 4000 style stoppers: the inside of a bottle doesn’t taper so the stoppers with very little taper are a better choice.
stainless wine stopper the best on the market