Features: 1) Easy to operate on/off switch; place drink on coaster to start flashing lights, when drink is removed lights turn off 2) Bulbs: 3 x 5mm red, blue and green LEDs (chips sourced from Taiwan) 3) LEDs controlled by IC to create circulating rainbow color changing effect 4) Power: 3 x 1.5V 'AAA' alkaline batteries (included) 5) Lighting time: 40 hours 6) Casing colors: red, purple, green, amber, translucent 7) Product size: 27 x 93mm 8) Weight: 93g (with batteries)