Muselet
A wire cage that fits over the cork of a bottle of champagne, sparkling wine or beer to prevent the cork from emerging under the pressure of the carbonated contents.
The muselet was invented in 1844 Adolphe Jaqueson to improve the seal on champagne bottles. The design has been improved over the years with the use of twisted steel wire for added strength and a metal cap.
The word is derived from the French museler, to muzzle.