The ornamental design for a squeezingdevice for collapsible flexible tubes, as shown and described.
FIG. 1 is a front elevation view of a squeezing device for collapsible flexible tubes showing my new design, the opposite side being a mirror image of the shown;
FIG. 2 is a bottom plan view thereof;
FIG. 3 is a top plan view thereof;
FIG. 4 is an isometric view thereof; and,
FIG. 5 is a right elevation view thereof, the opposite side being a mirror image of the shown.