The ornamental design for an O-shaped caution tape holder, as shown and described.
FIG. 1 is a perspective view of an O-shaped caution tape holder;
FIG. 2 is a front elevational view thereof;
FIG. 3 is a rear elevational view thereof;
FIG. 4 is a left-side elevational view thereof;
FIG. 5 is a right-side elevational view thereof;
FIG. 6 is a top plan view thereof;
FIG. 7 is a bottom plan view thereof; and,
FIG. 8 is a perspective view thereof, shown in its environment.
The broken line showing of a traffic cone in FIG. 8 is included for the purpose of showing environmental structure and forms no part of the claimed design.