What is it used for?

Canvas Clips are used to secure your canvas (stretched across framing bar) image inside the frame.

How do I use the canvas clips?

The canvas clip has two different edges.  The edge that has the pointed spikes is placed against the frame.  The edge that wraps around the stretcher bar has a rounded edge.

Place your canvas inside the frame. Take a canvas clip and slip the pointed spike edge between the canvas and the frame, forcing it down toward the center of the frame. (This is difficult the first few times you do it.)  Then you push the remaining part of the canvas clip back over the other edge of your canvas image. 

Note: Not all stretched canvas images can be fixed into the frame using the canvas clips.  Depending on the width and height of your stretcher bar, you may need to use offset clips instead.