Butterfly "This is PLASTIC ... not glass as stated. It is 7/8 inch high, with an opening of 5/32 inches, and a bottom of 3/8 inch wide, and a clear sticker for the measuring lines. You will have to file down the parts where it was attached to the mold with a nail file. It stands on its own and doesn't wobble. The reason for the low rating is because all of my lab accessories are glass, and this is advertised (and priced) as glass, but it is plastic. It looks cheap next to the other items. "