A nice charity shop find today, i'm pretty sure these are Powell Poppy Head wine glasses, beautifully made with vertical ribbing a plain stem and Wrthen twist pattern to the foot.
None described seem to have exact measurements, there is no shear mark, rough or polished pontil. four pinch marks to the bowl.
5 3/4 inches in height, 2 1/2 inches across the rim and 2 6/8th inches across the base.