UL -U-ground Outlet Wiring Tester (110 Volt) Ingenious receptacle tester instantly shows circuit status for individual outlet 3-light display shows open ground, open neutral, open hot Hot/ground reversed, hot/neutral reversed and correct wiring configuration Essential safety/diagnostic tool; works with any 110-125V 3-prong outlet Small enough to carry in pocket; keep one in each tool kit at home and work