Contigo Extreme Travel Mug Replacement Lid, Black/Square Tab;

This lid has a unique square tab that fits the Extreme Stainless Travel Mugs. Simply pull back the tab to drink, then seal to close. This lid helps keep drinks sealed; Perfect for your on-the-go lifestyle. Top rack dishwasher safe. This lid will fit the Contigo brand Extreme travel mugs that were purchased AFTER March 2010. I know, it was a long time ago. The other clue is to look and see if your lid has a square or a round tab. If it's square, then you've got the right replacement.