Durable & Rustproof Materialthe Universal Bottle Cap Is Made of High Quality Zinc Alloy Material and Organic Silicon Material. They Are Sturdy, Non-Slip, Rust-Proof, Corrosion-Resistant, and The Size Fits The Bottle Neck Perfectly. and The Silicone Is Made of Food Grade Silicone Material. You Can Use The Wine Stopper for A Long Time. .Keep Wine Freshthese Stainless Steel Wine Stopper Can Help You Keep Your Wine Fresh. When You Drink Alone, You Don'T Have To Worry About Drinking Incomplete Bottles. With A Wine Stopper, You Can Also Next Drink Fresh Wine All Day Long. .Easy To Use Simply Slide The Stainless Steel Wine Stopper Into The Top of Your Wine or Liquor Bottle. No More Fighting With Corks. .Multifunctional Specifications Flexible Specifications Make The Wine Stopper More Useful, Suitable for 15-20Mm Diameter Bottles, You Can Save Money and Time Without Buying Other Sizes of Wine Stopper.