This 4 pack of rainbow finger beams uses multiple color-changing LEDs that automatically cycle through various pattern speeds, alternating from a slow "mood" pattern that fades between colors to a fast pattern that flashes between each color. The different plastic case colors of each of the 4 lights also makes the LEDs light up uniquely. These lights do not have a steady-on function. Each Finger Beam utilizes an elastic strap to fit all size fingers. Each Finger Beam uses 3 long-lasting AG3 batteries (included and installed).