Solar stud is a best seller and has a big market in every country. Come-and-go roadway without zone isolation and light in shortage Crossroad / zebra stripes ( sign for speed-down) Urgent turning More fog area ( seaside, airport road ) Freeway and place without road lights Tunnel entrance and exit Railway ramp port On roadway line of toll station More traffic place Footpath, parkway etc, which are needed decorating night piece, road.