I had trouble with the first few, especially one larger jar. I examined and cleaned it, and used its original top, and then one of yours, but it would not seal. So I went out and bought a few of different sizes from a brand called Kates Kitchen and they worked. So, a bad start but a good finish. I love how it keeps the strawberries and Blueberries fresh for days. I do have a suggestion for design of the opening tool. It needs a wider head that presses up against the top when removing. This can a