1. Please note: Our lids are compatible with 40 oz Stanley cups that have a threaded inner rim. They are not suitable for Stanley cups with a smooth inner rim. Please check your cup's rim before . Thank you for your support! 2. 40 oz Stanley Cup Replacement Lid: This accessory is designed for the 40 oz Stanley Quencher tumbler. The FFF lid serves as an ideal replacement for the original Stanley Cup lid, effortlessly meeting your lid replacement needs. It provides a complete solution for cup enthusiasts seeking quality and convenience. The replacement lids fit on 40 oz Stanley cups with handles. 3. LeakProof Dustproof: Our Stanley flip straw replacement lids are engineered to prevent liquid spills and keep your cup clean. Once securely fastened, they create a tight seal to protect your drinks from leakage. You can also use the lid to cover the cup and prevent dust from entering, ensuring your beverage stays fresh anytime. Enjoy peace of mind while using and storing your mug. 4. Reusable Durable: These 40 oz replacement lids are built for longterm use, offering a reliable accessory for your Stanley cup. Made from quality materials, they are sturdy and wearresistant. The Stanley cup accessories, including straws and lids, are easy to disassemble for handwashing or dishwasher cleaning. Simply remove the straw, open the lid, and clean every corner thoroughly. 5. Practical Versatile: The leakproof Stanley cup lid allows you to enjoy your favorite drinks anytime by flipping the straw open—no need to remove the entire lid. Our insulated lids fit snugly on insulated cups, featuring thermal retention to keep your beverages hot or cold as needed. The durable flip straw makes drinking water, juice, milk, tea, or other beverages effortless, whether at the gym, in the car, or on a hike.