Product review (1 stars): Incorrect locking collar.
I have an RS2578WW/XAA fridge, and Amazon's part selector came up with this filter.

It does not fit.  I have attached pictures from Samsung's webpage titled
"RFG299AARS/XAA Replacement Filter Does Not Fit".

Notice the locking ring on Samsung has pointed tips.
This third party filter does not have those.

My old filter looks just like the proper kind from Samsung's webpage.
The filters I got from this order look like the incompatible kind.
I cannot mount them at all, and I'm not going to force the wrong one into place.

In the past, Waterdrop brand was just like Samsung's, but that product was discontinued.
I'm trying the current Waterdrop product, and hope to have better luck there.