J.LUMI YCA1008 is the next generation twist lock photocell sensor. Instead of using dated thermal mechanism, our photocell sensor features next generation electronic circuit board. It is ideal for 208-277 VAC light fixtures with ANSI C136.10 NEMA turn lock receptacles commonly found on dusk to dawn type barn or post lights. It provides dusk-to-dawn lighting control and saving energy when controlling exterior lighting, street and parking lot lighting. Built-in delay eliminates the load temporarily switching off due to car headlights, lightning or another temporary light source. Turn lock design using industry standard prong plugs makes this sensor easy to remove and install if replacement is needed.