Contigo Astor Autoseal Replacement Travel Mug Lid - Gray This lid fits the 16 oz. and 20 oz. AUTOSEAL Astor Stainless Travel Mug or the 16 oz. and 20 oz. AUTOSEAL Aria Stainless Travel Mug These Travel Mugs mentioned above are the only AUTOSEAL Stainless Travel Mugs that have a button that slides downward to lock, preventing the button from being accidentally pressed when not in use. If your mug does not currently have a button that slides down to lock, this lid will not fit your mug BPA-free lid | Top rack-dishwasher safe Designed to be spill and leak proof Easy, one-handed drinking with the push of a button