The Solar Post Cap Light has the classical look of a stained-glass shade. It lights up at night using energy stored during daylight hours. It"s designed to fit standard 4" or 3-1/2" wood or vinyl posts on outdoor decks, porches, patios and fences. The light begins to glow automatically at dusk. It"s easy to mount and maintenance-free. Has screw ports for permanent installation (screws included). Polypropylene. Measures 6-1/2" sq. x 3-1/2" with a 3-1/2" sq. bottom opening.Lovely outdoor lighting with an artistic designLooks like real stained glassLights up automatically at night...no electricity needed!Details:6-1/2" sq. x 3-1/2" with a 3-1/2" sq. bottom opening.Polypropylene