The Coravin™ System expands your opportunity to explore wines of any vintage, variety, winemaker, or wine growing region, all by the glass. You now have the freedom to access any wine, any time, in any quantity without ever pulling the cork. And go back to your favorites again and again for months or years.
The concept is simple, but the instrument is highly sophisticated. There is a hypodermic needle that punctures the capsule and cork, guiding it into the bottle precisely on a track. There is a regulator, activated by a trigger, that pumps argon into the bottle through the needle, pressurizing the bottle with this heavy inert gas. When tipped, the pressure forces wine back through the needle and through the pour spout. When finish pouring, you tip the bottle up and the excess argon is released into the air. You draw the needle out with the handle. The cork, being naturally resilient, reseals, admitting no oxygen into the bottle.
It is amazingly easy to use and comes with two argon gas cannisters that last a surprisingly long time. As you become more familiar with the device, you use less and less gas. You can even view a tutorial, below.