The ornamental design for a tubing with channel, as shown and described.
FIG. 1 is a perspective view of a tubing with channel showing our new design;
FIG. 2 is a front elevation view thereof;
FIG. 3 is a rear elevation view thereof;
FIG. 4 is a top plan view thereof, the bottom plan view being identical thereto; and,
FIG. 5 is a side elevation view thereof, the opposite side elevation view being a mirror image thereof.
The tubing is shown with a symbolic break in its length, represented by break lines. The appearance of any portion of the article between the break lines forms no part of the claimed design.