... type, square type, many different models3. 1 CR2032 button cell, 4 leds, red/green/blue/yellow all are available ... on). 2. Some led light machines are with button, once pushed, it can flash in several colours ... songs. 3. Some led light machines are without button, by shaking, it can flash in colours. Most ... sing songs by slightly shaking or pushing the button.Led light machine is also applied in shoes, ...