I think I have a Hayward Jet Air III. When closing the pool today, I realized that the fittings were not installed, but I found a few spare parts that look right here (SP1434-B, SP1434-D, SP1434-T). I used either a size 11 or 12 rubber plug, which got pushed in a little too deep, and I was unable to get it out. It stopped the air but I fear the difficulty at next year's opening.. What's the correct winterizing plug to use for this return? Is the rubber plug OK or do I need something like this?