We needed some supports for glass shelves resting on Knape & Vogt 14" metal brackets in a display cabinet. We designed these in SolidWorks. We printed them as a set of 4 (left front, right front, left rear, right rear). Originally all 4 were unique parts, but we simplified the rear brackets so now the left and right rears are identical parts. We had to do a tiny bit of filing in the groove to get the fit exact on the metal brackets. The 3/8" diameter hemispherical self-adhesive rubber feet were something we had laying around from a previous project.