The top unit with handle attaches to a wet canvas. Then place another canvas, wet or dry, facing the wet canvas. The unit keeps the two canvases 1/2" apart. A second unit fastens at the bottom. Fits any size canvas. Empty, the unit will fit in the bottom of a sketch box.

The top unit with handle attaches to a wet canvas. Then place another canvas, wet or dry, facing the wet canvas. The unit keeps the two canvases 1?2" apart. A second unit fastens at the bottom. Fits any size canvas. Empty, the unit will fit in the bottom of a sketch box.