Product Size: stopper is about 3.8CM Material: silicone Package includes: 6 stoppers 1. ECONOMICAL AND PRACTICAL: This set includes 6 black vacuum bottle stoppers. The pump removes air from the wine bottle, and the silicone stopper creates an airtight seal. 2. PRESERVE WINE FOR UP TO 10 DAYS: Designed to be used with wine preservation pumps. The pump and stoppers work together to remove air from your wine bottle, helping keep wine tasting fresh for up to 10 days. 3. DATE TRACKING FEATURE: The vacuum wine bottle stopper allows you to record the date you opened the bottle by simply rotating the ring on the top of the stopper. 4. EASY TO USE: Insert the stopper into the bottle neck and use a pump to remove air until resistance is felt. The more liquid is in the bottle, the fewer pumps are needed. Pinch the tip to release pressure before removing the stopper. 5. UNIVERSAL FIT: Suitable for all red and white wines. Fits standard wine bottles securely.