ADJUSTABLE BASE DESIGN - We design these planter box brackets base with a slider bracket component which can adjust the length of base rail to fits all kinds of flower boxes with minimum 6'' and the maximum 12'' depth ( Front To Back) .STURDY & DURABLE - Our wall mounted flower box brackets are made of good-quality and extra thickness iron with Black powder-coated finish. The brackets are designed to holds weight up to 40 lbs.WIDE APPLICATION - The Anti-rust and Anti-corrosion design planter box brackets can be used both indoors or outdoors. The brackets are affixed individually on the wall or under window or bolted to the railings of a porch or deck and holding all kinds of planter box sturdy. You can easily add elegance to just about any space by planting indoor outdoor plants, flowers, vegetables and so on.