The seamless, tapered spout allows controlled, medium speed pouring for quart, liter, half gallon, 1.75 liter, gallon, and other bottles with wider openings. This pourer is known for its consistent pouring speed, provinding maximum accuracy when pouring by count. Which is why this pourer is preferred by master mixologists and the Flair Bartenders Association. The flexible poly-kork prevents leakage. The fins on the poly-kork are flexed upwards while in the bottle. After each use, soak for 10 minutes in warm, soapy water, and the fins will return to their original horizontal position for a secure fit time after time. To clean, soak in warm, not hot, soapy water for 10 minutes. Made in USA