A container (101) has a constant wall thickness vessel (102) with a valve (103) crimped on at a neck (104) in the vessel. The valve has a dispensing stem (105). The vessel is circularly cylindrical and formed with an groove (106) extending parallel with the length of the vessel, from a base (107) to the neck (104). When the container is lain on its sidewall (108), it will roll, changing its orientation, until the groove (106) is at the surface as shown in FIG. 7, with the groove in effect floating on the surface of the liquid, providing an indication of the actual quantity of content in the container.
