Upgrade a wooden bed frame with the stable support of steel crossrails and a heavy-duty center support. Much stronger than wooden slats, the Adjustable Center Support System adjusts to fit Full, Full XL, Queen, King and Cal King bed sizes. Three cross rails adjust from 42 to 84 inches wide and lock by tightening an attached clamp. Rails have pre-drilled holes for frame attachment. The center support length can be adjusted for customized support, and three legs on the center support adjust in height. Use the included allen wrench to adjust leg height from 6.5 to 15.5 inches.