From the manufacturer: Play Kendama in the dark with LED lights. CATCHY® LED is a tough polycarbonate Kendama that lets you play into the night. The LED’s are a steady light (not blinking) to give a soothing glow and allows you to focus on the tricks. Catchy LED Kendama is molded from a strong and high impact polycarbonate built to withstand tough Kendama play. Built to Kendama specifications this is the first plastic Kendama to truly play up to par! Great for both the beginner to learn on or the advanced player for fun at night. The included batteries are easily replaceable and lights easily turn on and off with a switch.