These strobe lights have 4 high-intensity LEDs that flash in lowlight conditions. The built-in solar panel on top charges the NiMH battery even on cloudy days. On a full charge, the LEDs will flash continuously for 5 full nights, even without the sun to recharge. The strobe lights can be mounted with the included base, or inserted into cones with a 1 5/16" or larger top hole. It will not fit into all traffic cones, so check your cone's top hole diameter.