I have been making sausage for 40 years and decided the heavy cast machinery were getting just to heavy to deal with so I purchased the kitchenaid sausage stuffer kit. The design of the plunger is sheer incompetence and would most certainly have failed any real sausage making testing!  Who makes a plunger that is quartered and hollow, too small in diameter causing a large gap for the sausage to back up all the way to the handle. It's absolutely useless.  Start by sending your customers a real plunger!  Which by the way, a solid black plunger is used in your videos???