ADJUSTABLE BRIGHTNESS (NOTIFICATION: PLS REMOVE THE PROTECTIVE BACK FILM BEFORE USING IN ORDER TO MAKE THE PRODUCT TRANSPARENT.) Happy birthday neon sign has 3 smart buttons. The middle button controls the switch, and the up and down buttons can adjust the brightness (10%-100%). When you turn it off and then on again, the smart neon signs will restore to last state without press the button. PERFECT FOR ALL BIRTHDAY Use the happy birthday sign at the birthday party. After the birthday, you can use it as a room decoration light or night light. It can be used again for birthdays of family or friends and never goes out of style.