Most 40 fl oz straw tumblers list a 40 fl oz capacity and measure roughly 11.5 inches tall by about 5.4 inches wide. A few versions are slightly shorter—around 10.5 inches tall—while keeping a similar width.
They are primarily described for cold beverages and carbonated drinks. A few listings mention hot use, but detailed descriptions commonly state the tumblers are not recommended for hot beverages.