Creative Gift: This is a beautiful DIY electronic hourglass kit that is fun to make Double layer PCB: The kit adopts double layer PCB, which consists of 30 blue LEDs Simulated hourglass image: Under the control of the microcontroller program, the simulated hourglass image is displayed, which can be used as a decoration for the night light. Wide application: suitable for soldering skills training, DIY production, project design, electronic competition, holiday gifts, timer etc. It has the function of saving information after power off. After each function parameter setting, the data will be saved once, and the saved parameters will be executed next time the power is turned on. Instructions for forced initialization