An air conditioning unit is provided including a base pan having at least one hole surrounded by a first embossment including a first inclined sidewall and a first top wall. A mounting plate is positioned adjacent a portion of the base pan. The mounting plate has at least one opening surrounded by a second embossment including a second inclined sidewall and a second top wall. The at least one opening is generally aligned with the at least one hole. The second embossment overlays the first embossment such that a gap exists between the second inclined sidewall and the first inclined sidewall.