Vacu Vin Wine Saver Vacuum Stoppers are specially designed to be used alongside a genuine Vacu Vin Wine Saver Pump. These stoppers allow for an airtight vacuum that preserves the flavor and taste of wine for up to a week! The stoppers are universal for all bottles and are simply inserted into the neck of an opened wine bottle. Although they are most effective when used with a genuine Vacu Vin Wine Saver Pump, they can also be used as a traditional stopper, keeping additional air out!