This "sip" style lid is an accessory lid (purchased separately; water bottle not included) to enhance the hydrating experience of the 18 ounce Stainless Water Bottle. The lid fits securely on our 18 ounce bottle, and allows for easy sipping and drinking of hot or cold beverages (this lid does not have a straw attached). It can be opened/closed with a "one finger" flip. When you close it, there's a tiny rubber gasket that fits in the drink opening, which helps the lid to remain in the closed position fairly securely. You can hear it "click." And, when you flip it open, you can lock the lid in the open position by "clicking" it into place. Please note, however, that this lid is considered leak resistant and not leak proof.
The Flip Sip Lid measures approximately 8.5 inches in circumference (approximately 2.5 inches in diameter).
(Note: This lid will not fit our previously sold 12, 16 or 32 ounce Stainless Water Bottles)