This is a Knight Rider scanner that leaves a beautiful trail of light. It lights up immediately when DC power is supplied. The initial all-lights-on state can also be disabled. Supports a wide power supply voltage (5.5-16V). Reverse polarity protection built-in. 4 lighting patterns and speeds can be switched. The cord length is approximately 1m. This is a handmade product. Please comment if you have any other questions.