These brackets kept breaking that hold the drawer rails for our kitchen cabinets (see pic of original bracket). Decided to recreate it as best I could. I made the walls a little thicker so that they hopefully hold up a little better. I printed in PLA with 100% infill. You can play around with the resolution but I used .10mm.

Update 03/01/2016 - Printed one of these out last night at .10mm\100% infill. Fit was tight but it went on the rail. What I do is take the rail off, get the bracket started on the end of the rail. Then tap on the rail a couple times, test fit, tap some more, test fit. Do this over and over again until you have it seated to the correct length. Works great. With all this being said, you may or may not have the same experience printing them at a lower resolution. It may turn out to be a tighter fit or not fit at all.