The ornamental design for a removablesamplingport for a drain bag, as shown and described.
FIG. 1 is a top perspective view of a design for a removable sampling port for a drain bag;
FIG. 2 is a front view thereof;
FIG. 3 is a rear view thereof;
FIG. 4 is a left side view thereof;
FIG. 5 is a right side view thereof;
FIG. 6 is a top view thereof;
FIG. 7 is a bottom view thereof;
FIG. 8 is an exploded view thereof; and,
FIG. 9 is a side perspective thereof in a condition of use.
The broken lines depicting a drain bag and a tube in FIG. 9 represent environment subject matter and form no part of the claimed design, and the remaining broken lines in the drawings illustrate portions of the removable sampling port that form no part of the claimed design.