I've been seeing a number of different woodworkers warning not to use the plastic push sticks in the second photo, because they are dangerous. Instead, they suggest a plywood one, of the type I made and show in the first picture. The question is, what's so dangerous about the plastic ones? They don't really say. I can see two potential problems with the plastic push sticks. First, they will break much easier than plywood. I got one caught in a saw blade and it literally shattered. Apparently the manufacturer of that particular stick chose a plastic type that was brittle. Oops. But there's a more serious issue, in my eyes. That is, if your stick slips, your hand is headed right for the blade. As best I can tell, that can't really happen with the plywood one. Even if you tip it over and your hand lands on the table, it should be past the blade. There's another big advantage I see to this design as well. That is, you're not only pushing the material through the saw, but you're pushing down on the material, helping to hold it flat against the saw table, which should help reduce the risk of kickback and other problems. It only takes 20 to 30 minutes to make, so print out the plans and pattern (the PDF file) and make yourself one.