Based on your description, you’re referring to a specific type of laboratory flask, likely a volumetric or round-bottom flask with a long neck, a funnel-shaped top, and a ground glass stopper. Here’s a concise breakdown of the flask’s specifications and some clarifications.

The flask is 243mm in total height, having a bulb of 90mm Dia of 250ml approximate capacity. The long neck of a flask has at top a funnel of 50mm Dia in which fits a ground glass stopper. The neck has overall 11mm I.D. upper portions graduated from 18, 19, 20, 21, 22, 23, 24ml with 1ml graduation.