I have owned 6 Invisibelts and have literally worn them out.  I do not know how any woman dresses daily without one.  They not only hold your pants up perfectly, but they also smoothe out the button area.  Also, for those who wear belts that are not "just right" often have "muffin tops."  This solves that!
I also like it because I can buy pants a size too big so they are loose like I like them, but then the Invisibelt makes the waist fit perfectly.
Invisibelts should be offered in Every store...