The Large Sign Stands are designed for rigid substrates from 1/2" up to 2" in thickness. Sold in PAIRS, these sign stands are pre-drilled for placement of a through bolt (not included) to accommodate the exact thickness of your sign. At least One pair (4 legs) of Large Stands are required per sign and, for signs over 3' Wide, recommended spacing is max. 2' between each leg (this item can be purchased individually - call for details)