I bought this for my Ersatzdeckel Isosteel 0.75l bottle. He's just like the first original cover and fits exactly on the bottle. For the price I think you can not afford a replacement lock and does not have the same buy a new bottle / pot. Good thing there is this substitute stopper, as I have read, heard that not all companies offer. For price and closing I can only awarded 5 stars and am glad that I can use my vacuum flask back and forth.