Shelves need to be leveled in two directions. One axis is along the surface of the wall and the other axis comes out from the wall at a 90-degree angle. If you are installing the shelves for the first time, this is a very important consideration, for if you do not install shelves that are level, you may have to take them down and adjust the brackets that support the shelves.
Hold the four-foot level vertically against the wall, where you plan to hang install your shelves. If the wall is plumb, your shelf brackets will be level as they protrude out from the wall.
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