@TechConnectify@mas.to I felt exactly the same, when we had some of our doors replaced, it turned out 1 of them was a self-closing firedoor (working with a totally different mechanism, a strange hinge that forced the door to close on its own), since it was a self-closing fire door it had to be replaced with one, and I had to learn about door closers since that was the modern requirement. Thank you for your genuinely informative videos ❤️