Product review (5 stars): Fit Kenmore 578.144531
Some people have been unhappy that these filters have a glue line on both sides that prevent it from flexing into a C shape which is needed to fit into the filter holder.  They are a bit stiff but they definitely fit.  They appear to be the paper type, no shiny foil in them.  the sides are honeycomb.  I haven't used them yet but they fit and are good quality.