12" Flower Pot Holder with Special screw mounting brackets clasp to VERTICAL wood balusters. Great for apartment home railings, decks, fences and porches. Fits 1" to 1-1/2" square balusters / spires. The brackets are made with specially formed 1/8" thick steel plate which provides superior holding capability. Very simple and easy to install with only a screw driver.Powder coated 7/16" square steel.