FIG. 1 is a perspective view of the river surfboard showing the new design;
FIG. 2 is a front elevation view thereof;
FIG. 3 is a rear elevation view thereof;
FIG. 4 is a right side elevation view thereof;
FIG. 5 is a left side elevation view thereof;
FIG. 6 is a top view thereof; and,
FIG. 7 is a bottom view thereof.
The dashed lines refer to environment for illustrative purposes only and form no part of the claimed design. The dotted shading and thin broken lines represent three-dimensional contours, is for illustrative purposes only, and forms no part of the claimed design.