A pile of thin strips of wooden wedges.

A shim is a thin strip of material, often wedged in a space to raise up or stabilize a unit. In the world of windows and doors, shims are used during the installation process to ensure a window or door is plumb and level.

For 10 easy steps to install a window, go to www.youtube.com/watch?v=3MfqwtTHDRM.

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