We claim the ornamental design for a display base with flip book, as shown.
FIG. 1 is a perspective view of the display base with flip book in a first environment showing our new design;
FIG. 2 is a top plan view thereof;
FIG. 3 is a bottom plan view thereof;
FIG. 4 is a front elevation view thereof;
FIG. 5 is a rear elevation view thereof;
FIG. 6 is a right side view thereof;
FIG. 7 is a left side view thereof; and,
FIG. 8 is a perspective view of the display base with flip book in a second environment.
The broken line showing of details in FIGS. 1-8 is included for the purpose of showing environmental portions of the display base with flip book and forms no part of the claimed design.