It was disappointing that it was the same as the diameter of the sample wide-mouth clear bottle. It would be nice to use it as long as the lowest part of the upper door narrows the inner diameter a little. People who use a wide mouth think that the diaphragm diameter is not a problem because the container is also large to some extent.
Search for drums and order the largest. The lower diameter of the funnel was larger than the mouth of the drum and was not usable. Although it may be careless of you as the dimensions are described in the item description. . . That's too bad.