It takes a bit of effort to push down and screw in the knobs. More difficult if you happen to have any arthritis in your hands, like I do. Once attached it works well to tilt the canvas without getting paint on your hands. I found it was a bit cumbersome to find, grab and use the handles to turn the canvas. The handes often got in the way. I was hoping this would add ease to paint pouring, but it actually makes it a bit troublesome instead. I will not be using these again. Push pins are quicker and easier.