One of our best-selling items. Deck Prisms provided a safe source of natural sunlight to illuminate areas below deck on sailing ships in the days before electricity. Today they can be used in window sills and as paper weights and still refract light in the same fashion. These prims as approximately 2.75 inches wide by 3 inches tall and are available in 8 colors - clear, cobalt, green, cranberry, light blue, light green, red and turquoise. Please indicate your color choice.