j.lumi yca1008 twist lock photocell for outdoor lights, ul listed, next gen electronics, photocell for outdoor lights, twist lock photo control light sensor, dusk to dawn light sensor, blue j.lumi j.lumi yca1008 is the next generation twist lock photocell sensor. instead of using the dated thermal mechanism, our photocell sensor uses the next generational electronics to trigger the on/off of your lighting. 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. this photo control provides dusk-to-dawn lighting control and saving energy when controlling exterior lighting, street and parking lot lighting. built in delay function 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.