You've probably figured it out by now, but yes, those bits go approx 10" or so from the filter inlet / outlet. They are the shut of valves for when you need to clean the tank / filter.
When cleaning the filter for the first time (after the first couple of months), remember to release those valves once it's in the bathtub (or wherever you do your maintenance) - or else the vacuum will keep it shut no matter how hard you push or pull or twist
But be gentle with the little arms - I broke one once