2 stage skimmer basket

I was wondering what is the purpose for a "2 stage skimmer basket", if that makes sense. I have a skimmer basket and there's another part that slips into it a few inches, then a turn, then it will completely bottom out. In the skimmer, the inner one floats, for some reason. Not sure why. Mine likes to get hung up by binding with the outer one, and then it won't float on top of the water. Any reason for that inner basket? Can I just use the larger on to fit in the skimmer? Hope this makes some kind of sense to someone...heheh
Thanks in advance !

RockG in SC

Never seen that. Seems like a skimmer sock would do the same intended job, only better.

That basket is like mine. The floating inner part is basically a weir. It has an air pocket under the top lip to let it float. When the pump shuts off it keeps crud from floating back into the pool. Yes, mine sticks too at high water levels. You can run without it but you rn the risk of creating a vortex and sucking air into the suction line. Way around this it to put a rock or something in the bottom of the big basket to break up the water flow. Any sinkable irregular shaped object will do. I take that floating thing out when I vacuum a lot of debris because the large basket by itself provides more catch space. To prevent the sticking I rigged a thing on the skimmer cover to limit how high the inner part can float. Defeats the weir function though but even if it doesn't float all the way it still provides enough skimmer action. If you keep the water level about mid skimmer opening there should be no problem. I routinely let mine get near the top of the skimmer opening.
Al

Thanks Carl and Al, that's exactly what I have then. Might try the rock idea. I keep the water lever midskimmer, but when the thing binds, it sticks at the top, making water have to spill over the top to enter the basket. Pain and I have caught it not priming because the pump isn't getting enough water. I never could figure out what it was for though.

Thanks again !!

RockG in SC