Sixteen panels double the enclosure of the eight-panel version, which is what a larger dog or a shared garden needs - the same 21 x 31.5 in panels, twice as many of them. Shape them into a wide pen, a long fence or a divided training area. A 14.5 x 30.5 in door opens without dismantling the run. HDPE resists scratching and hoses clean. It ships in two cartons and needs no tools to put together. Black, with white also offered. Suitable indoors on a floor or outdoors on grass.