Nuvo Iron 2 1/2″ x 2 1/2″ Post Cap Pyramid Ornamental Aluminium for 2 1/2″x 2 1/2 metal posts If you’re looking for a 2.5″ 2.5″ post cap, we got you covered because this Nuvo Iron pyramid ornamental aluminium post cap tops both fence posts and deck posts. Its marine-grade