I may be able to measure my casings later today. If you don't have great hand strength, as with me, and find the rods difficult to snap on, you can loosen them. I took one to the hardware store and purchased dowels they would clamp onto. At home I soaked the red snappers in hot water in the bathtub to soften them up, then my dh snapped them onto the dowels. I left them for a couple of weeks (I think a few days would be enough!). This makes them not so tight, so it easier for me to use them. It also helps if your front loader is long enough to be laid on the table behind your machine, so you can use your whole body to press down on the snappers.