PG19 the largest size in the kit and the ONLY size I need. Unfortunately the hole is smaller than described (see photo), it says 16mm, but the actual size was 15.22mm. I needed 16mm so my cable wouldn't fit as it's too big for the smaller diameter. The outer diameter of the thread was measured at 23.92 mm. that fits for 26mm = 1.02 inch hole. I don't need the other sizes so I didn't measure. All items were scattered in the box. We combine the washer and parts to ensure you choose the correct quantity. It took time and the bulge of the container to fit them.