RoadStar Internally Illuminated Solar Pavement Levelled Markers/Studs Flush Type GI05 Bi-Directional products typically use the Light Emitting Diodes (LEDS) equipped with solar panels, LED bulbs, and durable battery. Our product passed all required laboratory tests and evidently the same are KTL, ONETECH, SGS, LCS, and DPWH-BUREAU and RESEARCH