PGFUN2 Pack Polaris Bags All Purpose Filter Bag Polaris Replacement Parts for Pool Cleaner for Polaris 360, 380,K13, K16

Does it lock on and fall off easily?

How do you remove these from pool sweep. I have an incredibly difficult time removing it without having to rock it too hard to remove it

how can i find the model number of my polaris?>>

I need to return mine as it is three inches across and i need four inches. how and where do i return it? and is it possible to get the four inch bag?