Shelf Hangers - 12" Wide X 12" Tall [4 Pack] Holds 350 lbs per vertical column of hangers. Simple hook through contruction allows you to effortlessly hang shelves from each other Skip shelf boards to create "double tall" shelves. Accomodates 12" wide plywood, melamine, or 1 X 12's Hang 3 columns of shelf hangers for longer boards.